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The CORRECT answer is (c) Stack is the FIFO data structure

The best explanation: Stack FOLLOWS LIFO.

The correct CHOICE is (b) 350

For EXPLANATION: The postfix EXPRESSION is EVALUATED using stack. We will get the infix expression as

(5*(4+6))*(4+9/3). On solving the Infix Expression, we get

(5*(10))*(4+3)

= 50*7

= 350.

Correct option is (c) – +PQ * rt

Easy explanation - GIVEN Infix Expression is ((p+q)-(R*t))

(+pq)-(r*t)

(-+pq)(r*t)

-+pq*rt. Thus PREFIX expression is -+pq*rt.

Right answer is (d) Stack

The best EXPLANATION: The Stack data structure is used to convert INFIX expression to postfix expression. The purpose of stack is to reverse the order of the OPERATORS in the expression. It ALSO serves as a storage structure, as no OPERATOR can be printed until both of its operands have appeared.

Right option is (d) Stack

Explanation: In serial ACCESS memory data records are stored one after the other in which they are created and are accessed SEQUENTIALLY. In stack data STRUCTURE, elements are accessed sequentially. Stack data structure RESEMBLES the serial access memory.

The correct answer is (b) Stack

Explanation: In recursive algorithms, the order in which the recursive process comes back is the REVERSE of the order in which it GOES forward during execution. The compiler uses the stack data STRUCTURE to implement recursion. In the forwarding phase, the values of local variables, parameters and the return address are pushed into the stack at each recursion level. In the backing-out phase, the STACKED address is popped and used to execute the REST of the code.

Correct choice is (C) AB + CD* E – *F *G /

Best explanation: (((A+ B)*(C*D- E)*F) / G) is CONVERTED to postfix expression as

(AB+(*(C*D- E)*F )/ G)

(AB+CD*E-*F) / G

(AB+CD*E-*F * G/). THUS Postfix expression is AB+CD*E-*F*G/

Correct choice is (d) -18

The best explanation: Postfix EXPRESSION is (6*(3-(2+4))) which RESULTS -18 as output.

Right answer is (d) DATA TRANSFER between two asynchronous PROCESS

The EXPLANATION is: Data transfer between the two asynchronous process uses the queue data structure for SYNCHRONISATION. The rest are all stack applications.

Correct answer is (d) There is a SEQUENTIAL entry that is one by one

Easy explanation - In stack DATA structure, ELEMENTS are ADDED one by one using push operation. Stack follows LIFO Principle i.e. Last In First Out(LIFO).

Right answer is (a) OVERFLOW

For explanation: The stack is filled with 5 elements and pushing one more ELEMENT causes a stack overflow. This results in overwriting MEMORY, code and LOSS of unsaved work on the COMPUTER.

Correct ANSWER is (a) randomly

Easiest EXPLANATION - Elements in an ARRAY are accessed randomly. In Linked LISTS, elements are accessed sequentially.

The CORRECT OPTION is (a) 0

Best explanation: In general, Array Indexing starts from 0. Thus, the INDEX of the FIRST ELEMENT in an array is 0.

Right choice is (b) There are chances of wastage of memory space if elements INSERTED in an ARRAY are lesser than the allocated SIZE

To explain: ARRAYS are of fixed size. If we insert elements less than the allocated size, unoccupied positions can’t be used again. Wastage will occur in memory.

Correct answer is (d) EASIER to STORE elements of same data type

Easy explanation - ARRAYS store elements of the same data type and present in continuous memory locations.

Correct answer is (d) SPATIAL locality

Easiest explanation - Whenever a particular memory location is referred to, it is likely that the locations NEARBY are also referred, ARRAYS are stored as contiguous blocks in memory, so if you want to access array ELEMENTS, spatial locality makes it to access quickly.

The correct ANSWER is (B) Run-time

Easy EXPLANATION - ArrayIndexOutOfBoundsException is a run-time exception and the COMPILATION is error-free.

The correct choice is (C) int[][]arr;

To explain: The syntax to DECLARE multidimensional ARRAY in java is EITHER int[][] arr; or int arr[][];

Right answer is (b) CONTAINER of objects of SIMILAR types

The EXPLANATION is: ARRAY contains elements only of the same type.

Correct option: (b) EMPTY the FIRST jar by removing it one by one from the first jar and placing it into the SECOND jar and empty the second jar by placing all the rings into the first jar one by one

This is similar to performing dequeue OPERATION using push and pop only. Elements in the first jar are taken out and placed in the second jar. After removing the last element from the first jar, remove all the elements in the second jar and PLACE them in the first jar.

Correct option is (b) abc X+ de^F^ –

Easy explanation - GIVEN Infix Expression is a + b X c – d ^ e ^ f.

(a b c X +) (d ^ e ^ f). ‘–‘ is present in STACK.

(a b c X + d e ^ f ^ -). Thus the final expression is (a b c X + d e ^ f ^ -).

Correct answer is (B) 2

Easy explanation - In the entire parenthesis balancing method when the INCOMING token is a left parenthesis it is pushed into stack. A right parenthesis makes POP operation to DELETE the elements in stack till we get left parenthesis as top most element. 2 left parenthesis are pushed whereas ONE right parenthesis removes one of left parenthesis. 2 elements are there before right parenthesis which is the maximum number of elements in stack at run time.

The correct answer is (c) 3

Easiest explanation - In the entire parenthesis BALANCING method when the incoming token is a left parenthesis it is PUSHED into stack. A right parenthesis makes pop operation to delete the elements in stack till we get left parenthesis as top most element. 3 elements are there in stack before right PARENTHESES comes. THEREFORE, MAXIMUM number of elements in stack at run time is 3.