76 + Interview Questions in Application Of Stacks in Data Structures & Algorithms I Page 1 InterviewSolution

1.	Which of the following statement is invalid with respect to balancing symbols?(a) [(A+B) + (C-D)](b) [{A+B}-{C-[D+E]}](c) ((A+B) + (C+D)(d) {(A+B) + [C+D]}The question is from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThis question was posed to me in an interview for job.
Answer» RIGHT answer is (C) ((A+B) + (C+D) The best explanation: ((A+B) + (C+D) is invalid because the last close brace is not FOUND in the STATEMENT.

Discussion

2.	How many passes does the balancing symbols algorithm makes through the input?(a) one(b) two(c) three(d) fourMy doubt stems from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in an interview for job.
Answer» Correct choice is (a) one To explain: The BALANCING symbols algorithm makes only one PASS through the input since it is linear.

Discussion

3.	Is the given statement ((A+B) + [C-D]] valid with respect to balancing of symbols?(a) True(b) FalseThis key question is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms IThe question was asked in an interview for job.
Answer» Correct CHOICE is (b) False For explanation: The given statement is invalid with respect to BALANCING of symbols because the last bracket does not CORRESPOND to the OPENING braces.

Discussion

4.	An error is reported when the stack is not empty at the end.(a) True(b) FalseI need to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II have been asked this question in an internship interview.
Answer» The correct option is (a) True To explain: When the STACK contains ELEMENTS at the END, it means that the given string of parentheses is not BALANCED.

Discussion

5.	If the corresponding end bracket/braces/parentheses is encountered, which of the following is done?(a) push it on to the stack(b) pop the stack(c) throw an error(d) treated as an exceptionThis interesting question is from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThe question was posed to me during an interview.
Answer» Right option is (b) pop the STACK The explanation is: When the CORRESPONDING end bracket/braces/parentheses is encountered, the stack is POPPED. When an opening bracket/braces/parentheses is encountered, it is PUSHED on to the stack.

Discussion

6.	When the corresponding end bracket/braces/parentheses is not found, what happens?(a) The stack is popped(b) Ignore the parentheses(c) An error is reported(d) It is treated as an exceptionMy question is taken from Application of Stacks topic in division Application of Stacks of Data Structures & Algorithms II have been asked this question in class test.
Answer» CORRECT option is (C) An ERROR is reported Best explanation: When the corresponding END bracket/braces/parentheses is not found, throw an error since they don’t match.

Discussion

7.	What should be done when an opening parentheses is read in a balancing symbols algorithm?(a) push it on to the stack(b) throw an error(c) ignore the parentheses(d) pop the stackQuestion is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in my homework.
Answer» The correct answer is (a) push it on to the stack Best explanation: When an OPENING bracket/braces/parentheses is encountered, it is PUSHED on to the stack. When the CORRESPONDING END bracket/braces/parentheses is not found, throw an error.

Discussion

8.	Which of the following statement is incorrect with respect to balancing symbols algorithm?(a) {[()]}(b) ([ )](c) {( )}(d) { [ ] }The query is from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms II got this question by my school teacher while I was bunking the class.
Answer» CORRECT OPTION is (B) ([ )] For explanation: ([ )] is INCORRECT because’)’ occurs before the corresponding ‘]’ is encountered.

Discussion

9.	Which of the following does the balancing symbols algorithm include?(a) balancing double quotes(b) balancing single quotes(c) balancing operators and brackets(d) balancing parentheses, brackets and bracesThe doubt is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in class test.
Answer» RIGHT choice is (d) balancing parentheses, BRACKETS and BRACES Easiest explanation - The balancing symbols ALGORITHM using STACK only includes balancing parentheses, brackets and braces and not any other symbols.

Discussion

10.	Which is the most appropriate data structure for applying balancing of symbols algorithm?(a) stack(b) queue(c) tree(d) graphI want to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in homework.
Answer» The correct answer is (a) stack Best explanation: Stack is the most APPROPRIATE data structure for BALANCING symbols algorithm because stack follows LIFO principle (LAST In FIRST Out).

Discussion

11.	In balancing parentheses algorithm, the string is read from?(a) right to left(b) left to right(c) center to right(d) center to leftThis interesting question is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms II got this question by my school teacher while I was bunking the class.
Answer» Correct option is (B) left to right The best EXPLANATION: Any STRING is read by the compiler from left to right and not from right to left.

Discussion

12.	Which application of stack is used to ensure that the pair of parentheses is properly nested?(a) Balancing symbols(b) Reversing a stack(c) Conversion of an infix to postfix expression(d) Conversion of an infix to prefix expressionQuery is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThe question was posed to me in homework.
Answer» RIGHT choice is (a) Balancing symbols Easy explanation - Balancing symbols APPLICATION ensures that the pair of parentheses are PROPERLY NESTED while reversing stack REVERSES a stack.

Discussion

13.	What is the time complexity of balancing parentheses algorithm?(a) O (N)(b) O (N log N)(c) O (M log N)(d) O (N^2)I need to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II had been asked this question by my college professor while I was bunking the class.
Answer» The correct choice is (a) O (N) For EXPLANATION: The TIME COMPLEXITY of balancing parentheses ALGORITHM is mathematically found to be O (N).

Discussion

14.	What will be result if the given stack is popped?(a) pat(b) tap(c) atp(d) aptThis interesting question is from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in my homework.
Answer» The correct CHOICE is (b) TAP Easy EXPLANATION - The word ‘pat’ is PUSHED on to the stack. When the characters of the stack are popped one by one, the word ‘tap’ is obtained.

Discussion

15.	How many stacks are required for reversing a word algorithm?(a) one(b) two(c) three(d) fourMy query is from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms II got this question in homework.
Answer» The CORRECT OPTION is (a) one Explanation: Only 1 STACK is required for REVERSING a WORD using stack. In that stack, push and pop operations are carried out.

Discussion

16.	What will be the word obtained if the word “abbcabb” is reversed using a stack?(a) bbabbca(b) abbcabb(c) bbacbba(d) bbacabbI want to ask this question from Reverse a Word using Stack topic in chapter Application of Stacks of Data Structures & Algorithms IThis question was posed to me during an online exam.
Answer» Correct ANSWER is (C) bbacbba Easiest EXPLANATION - The string “abbcabb” is pushed on to the STACK. If the CHARACTERS are popped one by one, the word obtained will be bbacbba.

Discussion

17.	What is the time complexity of reversing a word using stack algorithm?(a) O (N log N)(b) O (N^2)(c) O (N)(d) O (M log N)I want to ask this question from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms II had been asked this question in class test.
Answer» Correct CHOICE is (C) O (N) For explanation: The TIME COMPLEXITY of reversing a stack is mathematically FOUND to be O (N) where N is the input.

Discussion

18.	Operations required for reversing a word or a string using stack are push() andpop().(a) True(b) FalseMy doubt is from Reverse a Word using Stack in portion Application of Stacks of Data Structures & Algorithms IThe question was posed to me in quiz.
Answer» RIGHT option is (a) True Explanation: PUSH operation inserts a CHARACTER into the stack and pop operation POPS the top of the stack.

Discussion

19.	Which is the most appropriate data structure for reversing a word?(a) queue(b) stack(c) tree(d) graphI'm obligated to ask this question of Reverse a Word using Stack topic in division Application of Stacks of Data Structures & Algorithms IThis question was addressed to me by my college director while I was bunking the class.
Answer» RIGHT choice is (b) stack Best EXPLANATION: Stack is the most appropriate data structure for REVERSING a word because stack FOLLOWS LIFO principle.

Discussion

20.	Reversing a word using stack can be used to find if the given word is a palindrome or not.(a) True(b) FalseQuestion is taken from Reverse a Word using Stack in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in final exam.
Answer» Right choice is (a) True To explain: This application of stack can also be USED to find if the GIVEN WORD is a palindrome because, if the REVERSED is same as that of the original word, the given word is a palindrome.

Discussion

21.	The result of the postfix expression 5 3 * 9 + 6 / 8 4 / + is _____________(a) 8(b) 6(c) 10(d) 9My doubt is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms II have been asked this question in an interview.
Answer» Right option is (b) 6 The best explanation: Given postfix expression:5 3 * 9 + 6 / 8 4 / + RESULT = 5 3 * 9 + 6 / 8 4 / +

Discussion

22.	Which of the following is valid reverse polish expression?(a) a op b(b) op a b(c) a b op(d) both op a b and a b opThis interesting question is from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThis question was posed to me during a job interview.
Answer» The correct CHOICE is (c) a b op The best EXPLANATION: The postfix expression is also known as the REVERSE polish expression. In postfix expressions, the operators come after the operands. So, the correct expression is a b op and hence a b op is correct.

Discussion

23.	To convert the postfix expression into the infix expression we use stack and scan the postfix expression from left to right.(a) True(b) FalseMy question is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms IThe question was asked in a national level competition.
Answer» The correct option is (a) True Easy explanation - Stack is used to POSTFIX expression to INFIX expression. And to convert we follow the following STEPS: (i) Scan the expression from left to right. (ii) If operand is found, push it on stack.(iii) If OPERATOR is found, the TWO operands are popped and the combined infix expression is formed and pushed onto the stack.

Discussion

24.	Consider the postfix expression 4 5 6 a b 7 8 a c, where a, b, c are operators. Operator a has higher precedence over operators b and c. Operators b and c are right associative. Then, equivalent infix expression is(a) 4 a 5 6b 7 8 a c(b) 4 a 5 c 6 b 7 a 8(c) 4 b 5 a 6 c 7 a 8(d) 4 a 5 b 6 c 7 a 8This intriguing question comes from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms II had been asked this question during an online exam.
Answer» Correct choice: (c) 4 b 5 a 6 c 7 a 8 Given POSTFIX EXPRESSION: 4 5 6 a b 7 8 a c INFIX ⇒ 4 (5 a 6)b (7 a 8)c ⇒ (4 b (5 a 6)) (7 a 8)c ⇒ (4 b (5 a 6)) c (7 a 8) So, the required infix expression is 4 b 5 a 6 c 7 a 8.

24.

Consider the postfix expression 4 5 6 a b 7 8 a c, where a, b, c are operators. Operator a has higher precedence over operators b and c. Operators b and c are right associative. Then, equivalent infix expression is(a) 4 a 5 6b 7 8 a c(b) 4 a 5 c 6 b 7 a 8(c) 4 b 5 a 6 c 7 a 8(d) 4 a 5 b 6 c 7 a 8This intriguing question comes from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms II had been asked this question during an online exam.

Answer»

Correct choice: (c) 4 b 5 a 6 c 7 a 8

Given POSTFIX EXPRESSION: 4 5 6 a b 7 8 a c

INFIX ⇒ 4 (5 a 6)b (7 a 8)c

⇒ (4 b (5 a 6)) (7 a 8)c

⇒ (4 b (5 a 6)) c (7 a 8)

So, the required infix expression is 4 b 5 a 6 c 7 a 8.

Discussion

25.	The prefix expression of the postfix expression AB+CD-* is __________(a) (A+B)(C-D)(b) +AB-CD(c) A+BCD-(d) +AB-CDThe doubt is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in an online quiz.
Answer» CORRECT answer is (d) +AB-CD To explain: To CONVERT from postfix to PREFIX, we FIRST convert it to infix and then to prefix. postfix :AB+CD- infix ⇒ (A+B) * (C-D) So,prefix ⇒ +AB*-CD,

Discussion

26.	What is the value of the postfix expression2 3 + 4 5 6 – – *(a) 19(b) 21(c) -4(d) 25This key question is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThe question was asked during an internship interview.
Answer» CORRECT option is (d) 25 The best EXPLANATION: Given postfix expression : 2 3 + 4 5 6 – – * infix ⇒ (2 + 3)4 (5 – 6) – * ⇒ (2 + 3)4 – (5 – 6) Hence, VALUE = (2 + 3) (4 – (5 – 6)) = 5 (4 – (-1)) = 55 = 25.

Discussion

27.	The equivalent infix expression and value for the postfix form 1 2 + 3 * 4 5 * – will be ___________(a) 1 + 2 * 3 – 4 * 5 and -13(b) (2 + 1) * (3 – 4) * 5 and 13(c) 1 + 2 * (3 – 4) * 5 and -11(d) (1 + 2) * 3 – (4 * 5) and -11My doubt stems from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question in an interview for job.
Answer» CORRECT answer is (d) (1 + 2) * 3 – (4 * 5) and -11 Given postfix expression : 1 2 + 3 * 4 5 * – ⇒ (1 + 2) 3 * 4 5 * – ⇒ ((1 + 2) * 3) 4 5 * – ⇒ ((1 + 2) * 3) (4 * 5) – ⇒ ((1 + 2) * 3) – (4 * 5) So, the equivalent infix expression is (1 + 2) * 3 – (4 * 5) and it’s VALUE is -11.

27.

The equivalent infix expression and value for the postfix form 1 2 + 3 * 4 5 * – will be ___________(a) 1 + 2 * 3 – 4 * 5 and -13(b) (2 + 1) * (3 – 4) * 5 and 13(c) 1 + 2 * (3 – 4) * 5 and -11(d) (1 + 2) * 3 – (4 * 5) and -11My doubt stems from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question in an interview for job.

Answer»

CORRECT answer is (d) (1 + 2) * 3 – (4 * 5) and -11

Given postfix expression : 1 2 + 3 * 4 5 * –

⇒ (1 + 2) 3 * 4 5 * –

⇒ ((1 + 2) * 3) 4 5 * –

⇒ ((1 + 2) * 3) (4 * 5) –

⇒ ((1 + 2) * 3) – (4 * 5)

So, the equivalent infix expression is (1 + 2) * 3 – (4 * 5) and it’s VALUE is -11.

Discussion

28.	The postfix expression abc+de/- is equivalent to which of the following infix expression?(a) abc+-de/(b) (a+b)-d/ec(c) a-(b+c)(d/e)(d) abc+*-(d/e)My enquiry is from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question during a job interview.
Answer» Right answer is (C) a-(b+c)(d/e) Easy explanation - Given POSTFIX expression : abc+de/- INFIX ⇒ a(b+c)(d/e)- ⇒ a(b+c)(d/e)- ⇒ a-(b+c)(d/e) Hence, CORRECT choice is a-(b+c)(d/e).

Discussion

29.	Which of the following data structure is used to convert postfix expression to infix expression?(a) Stack(b) Queue(c) Linked List(d) HeapMy query is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in a national level competition.
Answer» CORRECT option is (a) Stack Best EXPLANATION: To convert the POSTFIX expression into INFIX expression we need stack. We need stack to maintain the intermediate infix expressions. We use stack to hold operands.

Discussion

30.	Given two processes (conversion of postfix equation to infix notation and conversion of prefix notation to infix notation), which of the following is easier to implement?(a) Both are easy to implement(b) Conversion of postfix equation to infix equation is harder than converting a prefix notation to infix notation(c) Conversion of postfix equation to infix equation is easier than converting a prefix notation to infix notation(d) Insufficient dataThe origin of the question is Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThe question was posed to me in unit test.
Answer» The correct choice is (c) Conversion of POSTFIX equation to INFIX equation is easier than CONVERTING a prefix notation to infix notation Explanation: As the conversion of prefix notation to infix notation involves reversing the equation, the latter is harder to implement than postfix to infix PROCESS.

Discussion

31.	The time complexity of converting a prefix notation to infix notation is _________(a) O(n) where n is the length of the equation(b) O(n) where n is number of operands(c) O(1)(d) O(logn) where n is length of the equationQuestion is taken from Application of Stacks in section Application of Stacks of Data Structures & Algorithms IThe question was posed to me in a national level competition.
Answer» The correct ANSWER is (a) O(n) where n is the LENGTH of the equation Explanation: The processes that are INVOLVED are REVERSING the equation (O(n)), pushing them all onto the stack(O(n)), and popping them one by one and solving them (O(n)). Hence the answer is O(n) where n is the length of the equation.

Discussion

32.	When converting the prefix notation into an infix notation, the first step to be followed is ________(a) Reverse the equation(b) Push the equation to the stack(c) Push the equation onto the queue(d) Push the equation to the stack or queueThis intriguing question comes from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms IThe question was posed to me in a job interview.
Answer» The correct choice is (a) Reverse the equation The explanation is: The STEPS that are FOLLOWED are: the equation is reversed, pushed onto a stack, popped ONE by one and SOLVED. THEREFORE the first step is reversing the equation.

Discussion

33.	Given a prefix and a postfix notation what are the difference between them?(a) The postfix equation is solved starting from the left whereas the prefix notation is solved from the right(b) The postfix equation is solved starting from the right whereas the prefix notation is solved from the left(c) Both equations are solved starting from the same side(right)(d) Both equations are solved starting from the same side(left)My question is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms II got this question by my college director while I was bunking the class.
Answer» Right option is (a) The POSTFIX EQUATION is solved STARTING from the left whereas the prefix NOTATION is solved from the right The best explanation: The postfix notation is solved starting from left but whereas the prefix notation is reversed after creating them, therefore it’s solved starting from right.

Discussion

34.	From the given Expression tree, identify the correct postfix expression from the list of options.(a) abcd+(b) abcd-+(c) abcd-+(d) ab*+cd-The origin of the question is Application of Stacks in division Application of Stacks of Data Structures & Algorithms IThis question was posed to me in semester exam.
Answer» The correct option is (b) abcd-+ For explanation: From the given expression tree, the INFIX expression is found to be (ab)+(c-d). CONVERTING it to postfix, we GET, ab*cd-+.

Discussion

35.	In infix to postfix conversion algorithm, the operators are associated from?(a) right to left(b) left to right(c) centre to left(d) centre to rightThe above asked question is from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms II have been asked this question by my school principal while I was bunking the class.
Answer» The correct option is (b) left to right For explanation: In infix, PREFIX and POSTFIX expressions, the operators are ASSOCIATED from left to right and not right to left.

Discussion

36.	Which of the following statement is incorrect with respect to infix to postfix conversion algorithm?(a) operand is always placed in the output(b) operator is placed in the stack when the stack operator has lower precedence(c) parenthesis are included in the output(d) higher and equal priority operators follow the same conditionMy question is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms IThis question was posed to me during a job interview.
Answer» RIGHT choice is (c) parenthesis are INCLUDED in the OUTPUT The BEST I can explain: Parentheses are not included in the output. They are placed in the operator stack and then discarded.

Discussion

37.	It is easier for a computer to process a postfix expression than an infix expression.(a) True(b) FalseOrigin of the question is Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThe question was asked in quiz.
Answer» Right ANSWER is (a) True For explanation: COMPUTERS can easily PROCESS a postfix EXPRESSION because a postfix expression keeps track of precedence of operators.

Discussion

38.	Parentheses are simply ignored in the conversion of infix to postfix expression.(a) True(b) FalseOrigin of the question is Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II got this question by my college professor while I was bunking the class.
Answer» The CORRECT OPTION is (b) False For explanation: When a parenthesis is ENCOUNTERED, it is placed on the operator STACK. When the CORRESPONDING parenthesis is encountered, the stack is popped until the other parenthesis is reached and they are discarded.

Discussion

39.	What is the time complexity of an infix to postfix conversion algorithm?(a) O(N log N)(b) O(N)(c) O(N^2)(d) O(M log N)This is a very interesting question from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in unit test.
Answer» CORRECT choice is (b) O(N) The best I can explain: The TIME complexity of an infix to POSTFIX EXPRESSION conversion algorithm is mathematically found to be O(N).

Discussion

40.	Which of the following is an infix expression?(a) (a+b)(c+d)(b) ab+c(c) +ab(d) abc+*The above asked question is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms II had been asked this question by my school principal while I was bunking the class.
Answer» CORRECT ANSWER is (a) (a+b)(c+d) BEST explanation: (a+b)(c+d) is an infix expression. +AB is a prefix expression and ab+c* is a POSTFIX expression.

Discussion

41.	What should be done when a left parenthesis ‘(‘ is encountered?(a) It is ignored(b) It is placed in the output(c) It is placed in the operator stack(d) The contents of the operator stack is emptiedMy question comes from Application of Stacks in section Application of Stacks of Data Structures & Algorithms IThe question was posed to me in my homework.
Answer» The correct choice is (C) It is placed in the OPERATOR stack Easiest EXPLANATION - When a left PARENTHESIS is encountered, it is placed on to the operator stack. When the corresponding right parenthesis is encountered, the stack is popped until the left parenthesis and remove both the parenthesis.

Discussion

42.	Out of the following operators (\|, , +, &), the one having lowest priority is ________(a) +(b) (c) \|(d) &I would like to ask this question from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms IThe question was posed to me in an interview for an internship.
Answer» Correct option is (c) \| The EXPLANATION is: ACCORDING to the ALGORITHM (infix-prefix), it follows that the logical OR will have the LOWEST PRIORITY.

Discussion

43.	Out of the following operators (^, , +, &), the one having highest priority is _________(a) +(b) (c) ^(d) &My enquiry is from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question in quiz.
Answer» The CORRECT choice is (c) ^ The explanation is: According to the ALGORITHM (infix-prefix), it FOLLOWS that the EXPONENTIATION will have the highest priority.

Discussion

44.	What data structure is used when converting an infix notation to prefix notation?(a) Stack(b) Queue(c) B-Trees(d) Linked-listMy question is based upon Application of Stacks in division Application of Stacks of Data Structures & Algorithms II got this question during an interview for a job.
Answer» Right choice is (a) Stack For EXPLANATION: First you reverse the given EQUATION and CARRY out the ALGORITHM of infix to POSTFIX expression. Here, the data structure used is stacks.

Discussion

45.	For the given expression tree, write the correct postfix expression.(a) abc+(b) abc+(c) ab+c(d) a+bcI want to ask this question from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me during an interview for a job.
Answer» CORRECT answer is (a) ABC+ To explain: EVALUATING the given expression TREE GIVES the infix expression a+bc. Converting it to postfix, we get, abc*+.

Discussion

46.	Evaluate the postfix expression ab + cd/- where a=5, b=4, c=9, d=3.(a) 23(b) 15(c) 6(d) 10Question is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me by my college director while I was bunking the class.
Answer» Correct choice is (C) 6 The EXPLANATION is: The INFIX expression is (a+b)-c/d. EVALUATING it, (5+4)-9/3 GIVES 6.

Discussion

47.	What is the result of the given postfix expression?abc*+ where a=1, b=2, c=3.(a) 4(b) 5(c) 6(d) 7I need to ask this question from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in examination.
Answer» RIGHT OPTION is (d) 7 Best EXPLANATION: The infix EXPRESSION is a+bc. Evaluating it, we get 1+23=7.

Discussion

48.	Which of the following statement is incorrect?(a) Postfix operators use value to their right(b) Postfix operators use value to their left(c) Prefix operators use value to their right(d) In postfix expression, operands are followed by operatorsQuestion is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in an interview for internship.
Answer» Correct choice is (a) Postfix operators use VALUE to their RIGHT The best I can EXPLAIN: All prefix operators use values to their right and all postfix operators use values to their LEFT.

Discussion

49.	While evaluating a postfix expression, when an operator is encountered, what is the correct operation to be performed?(a) push it directly on to the stack(b) pop 2 operands, evaluate them and push the result on to the stack(c) pop the entire stack(d) ignore the operatorThis question is from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms II had been asked this question in homework.
Answer» Right CHOICE is (B) pop 2 OPERANDS, evaluate them and push the result on to the stack The explanation is: When an operator is encountered, the FIRST two operands are popped from the stack, they are evaluated and the result is PUSHED into the stack.

Discussion

50.	Which of the following is not an application of stack?(a) evaluation of postfix expression(b) conversion of infix to postfix expression(c) balancing symbols(d) line at ticket counterMy doubt is from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II have been asked this question by my school principal while I was bunking the class.
Answer» The correct answer is (d) LINE at ticket COUNTER Easy explanation - Line at ticket counter is an APPLICATION of queue WHEREAS conversion of infix to postfix expression, BALANCING symbols, line at ticket counter are stack applications.

Discussion

Explore topic-wise InterviewSolutions in .

How many passes does the balancing symbols algorithm makes through the input?(a) one(b) two(c) three(d) fourMy doubt stems from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in an interview for job.

Is the given statement ((A+B) + [C-D]] valid with respect to balancing of symbols?(a) True(b) FalseThis key question is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms IThe question was asked in an interview for job.

An error is reported when the stack is not empty at the end.(a) True(b) FalseI need to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II have been asked this question in an internship interview.

Which is the most appropriate data structure for applying balancing of symbols algorithm?(a) stack(b) queue(c) tree(d) graphI want to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in homework.

What will be result if the given stack is popped?(a) pat(b) tap(c) atp(d) aptThis interesting question is from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in my homework.

How many stacks are required for reversing a word algorithm?(a) one(b) two(c) three(d) fourMy query is from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms II got this question in homework.

What is the time complexity of reversing a word using stack algorithm?(a) O (N log N)(b) O (N^2)(c) O (N)(d) O (M log N)I want to ask this question from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms II had been asked this question in class test.

Operations required for reversing a word or a string using stack are push() andpop().(a) True(b) FalseMy doubt is from Reverse a Word using Stack in portion Application of Stacks of Data Structures & Algorithms IThe question was posed to me in quiz.

Reversing a word using stack can be used to find if the given word is a palindrome or not.(a) True(b) FalseQuestion is taken from Reverse a Word using Stack in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in final exam.

The result of the postfix expression 5 3 * 9 + 6 / 8 4 / + is _____________(a) 8(b) 6(c) 10(d) 9My doubt is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms II have been asked this question in an interview.

Which of the following is valid reverse polish expression?(a) a op b(b) op a b(c) a b op(d) both op a b and a b opThis interesting question is from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThis question was posed to me during a job interview.

The prefix expression of the postfix expression AB+CD-* is __________(a) (A+B)(C-D)(b) +AB-CD(c) A+BCD-(d) +AB-CDThe doubt is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in an online quiz.

What is the value of the postfix expression2 3 + 4 5 6 – – *(a) 19(b) 21(c) -4(d) 25This key question is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThe question was asked during an internship interview.

It is easier for a computer to process a postfix expression than an infix expression.(a) True(b) FalseOrigin of the question is Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThe question was asked in quiz.

Parentheses are simply ignored in the conversion of infix to postfix expression.(a) True(b) FalseOrigin of the question is Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II got this question by my college professor while I was bunking the class.

What is the time complexity of an infix to postfix conversion algorithm?(a) O(N log N)(b) O(N)(c) O(N^2)(d) O(M log N)This is a very interesting question from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in unit test.

Which of the following is an infix expression?(a) (a+b)(c+d)(b) ab+c(c) +ab(d) abc+*The above asked question is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms II had been asked this question by my school principal while I was bunking the class.

Out of the following operators (|, , +, &), the one having lowest priority is ________(a) +(b) (c) |(d) &I would like to ask this question from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms IThe question was posed to me in an interview for an internship.

Out of the following operators (^, , +, &), the one having highest priority is _________(a) +(b) (c) ^(d) &My enquiry is from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question in quiz.

What data structure is used when converting an infix notation to prefix notation?(a) Stack(b) Queue(c) B-Trees(d) Linked-listMy question is based upon Application of Stacks in division Application of Stacks of Data Structures & Algorithms II got this question during an interview for a job.

For the given expression tree, write the correct postfix expression.(a) abc+(b) abc+(c) ab+c(d) a+bcI want to ask this question from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me during an interview for a job.

Evaluate the postfix expression ab + cd/- where a=5, b=4, c=9, d=3.(a) 23(b) 15(c) 6(d) 10Question is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me by my college director while I was bunking the class.

What is the result of the given postfix expression?abc*+ where a=1, b=2, c=3.(a) 4(b) 5(c) 6(d) 7I need to ask this question from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in examination.

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How many passes does the balancing symbols algorithm makes through the input?(a) one(b) two(c) three(d) fourMy doubt stems from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in an interview for job.

Is the given statement ((A+B) + [C-D]] valid with respect to balancing of symbols?(a) True(b) FalseThis key question is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms IThe question was asked in an interview for job.

An error is reported when the stack is not empty at the end.(a) True(b) FalseI need to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II have been asked this question in an internship interview.

Which is the most appropriate data structure for applying balancing of symbols algorithm?(a) stack(b) queue(c) tree(d) graphI want to ask this question from Application of Stacks topic in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in homework.

What will be result if the given stack is popped?(a) pat(b) tap(c) atp(d) aptThis interesting question is from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in my homework.

How many stacks are required for reversing a word algorithm?(a) one(b) two(c) three(d) fourMy query is from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms II got this question in homework.

What is the time complexity of reversing a word using stack algorithm?(a) O (N log N)(b) O (N^2)(c) O (N)(d) O (M log N)I want to ask this question from Reverse a Word using Stack in chapter Application of Stacks of Data Structures & Algorithms II had been asked this question in class test.

Operations required for reversing a word or a string using stack are push() andpop().(a) True(b) FalseMy doubt is from Reverse a Word using Stack in portion Application of Stacks of Data Structures & Algorithms IThe question was posed to me in quiz.

Reversing a word using stack can be used to find if the given word is a palindrome or not.(a) True(b) FalseQuestion is taken from Reverse a Word using Stack in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in final exam.

The result of the postfix expression 5 3 * 9 + 6 / 8 4 / + is _____________(a) 8(b) 6(c) 10(d) 9My doubt is from Application of Stacks in division Application of Stacks of Data Structures & Algorithms II have been asked this question in an interview.

Which of the following is valid reverse polish expression?(a) a op b(b) op a b(c) a b op(d) both op a b and a b opThis interesting question is from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThis question was posed to me during a job interview.

The prefix expression of the postfix expression AB+CD-* is __________(a) (A+B)*(C-D)(b) +AB*-CD(c) A+*BCD-(d) *+AB-CDThe doubt is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in an online quiz.

What is the value of the postfix expression2 3 + 4 5 6 – – *(a) 19(b) 21(c) -4(d) 25This key question is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThe question was asked during an internship interview.

It is easier for a computer to process a postfix expression than an infix expression.(a) True(b) FalseOrigin of the question is Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThe question was asked in quiz.

Parentheses are simply ignored in the conversion of infix to postfix expression.(a) True(b) FalseOrigin of the question is Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II got this question by my college professor while I was bunking the class.

What is the time complexity of an infix to postfix conversion algorithm?(a) O(N log N)(b) O(N)(c) O(N^2)(d) O(M log N)This is a very interesting question from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me in unit test.

Which of the following is an infix expression?(a) (a+b)*(c+d)(b) ab+c*(c) +ab(d) abc+*The above asked question is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms II had been asked this question by my school principal while I was bunking the class.

Out of the following operators (|, *, +, &), the one having lowest priority is ________(a) +(b) *(c) |(d) &I would like to ask this question from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms IThe question was posed to me in an interview for an internship.

Out of the following operators (^, *, +, &), the one having highest priority is _________(a) +(b) *(c) ^(d) &My enquiry is from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question in quiz.

What data structure is used when converting an infix notation to prefix notation?(a) Stack(b) Queue(c) B-Trees(d) Linked-listMy question is based upon Application of Stacks in division Application of Stacks of Data Structures & Algorithms II got this question during an interview for a job.

For the given expression tree, write the correct postfix expression.(a) abc*+(b) abc+*(c) ab+c*(d) a+bc*I want to ask this question from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me during an interview for a job.

Evaluate the postfix expression ab + cd/- where a=5, b=4, c=9, d=3.(a) 23(b) 15(c) 6(d) 10Question is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms IThis question was addressed to me by my college director while I was bunking the class.

What is the result of the given postfix expression?abc*+ where a=1, b=2, c=3.(a) 4(b) 5(c) 6(d) 7I need to ask this question from Application of Stacks topic in chapter Application of Stacks of Data Structures & Algorithms IThe question was asked in examination.

The prefix expression of the postfix expression AB+CD-* is __________(a) (A+B)(C-D)(b) +AB-CD(c) A+BCD-(d) +AB-CDThe doubt is from Application of Stacks in portion Application of Stacks of Data Structures & Algorithms II had been asked this question in an online quiz.

Which of the following is an infix expression?(a) (a+b)(c+d)(b) ab+c(c) +ab(d) abc+*The above asked question is from Application of Stacks in section Application of Stacks of Data Structures & Algorithms II had been asked this question by my school principal while I was bunking the class.

Out of the following operators (|, , +, &), the one having lowest priority is ________(a) +(b) (c) |(d) &I would like to ask this question from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms IThe question was posed to me in an interview for an internship.

Out of the following operators (^, , +, &), the one having highest priority is _________(a) +(b) (c) ^(d) &My enquiry is from Application of Stacks in chapter Application of Stacks of Data Structures & Algorithms II have been asked this question in quiz.

For the given expression tree, write the correct postfix expression.(a) abc+(b) abc+(c) ab+c(d) a+bcI want to ask this question from Application of Stacks topic in section Application of Stacks of Data Structures & Algorithms IThis question was addressed to me during an interview for a job.