Abhishek is taking exam on N subjects. The score on each subject will be an integer between 0 and K (inclusive) He has already taken exams on N - 1 subjects and scored A[i] points on i-th subject His goal is to achieve the average score of M points or above on the N subjects print the minimum number of points Abhishek needs on the final subject to achieve the goal if the goal is unreachable , print -1 instead?

Abhishek is taking exam on N subjects. The score on each subject will

1.	Abhishek is taking exam on N subjects. The score on each subject will be an integer between 0 and K (inclusive) He has already taken exams on N - 1 subjects and scored A[i] points on i-th subject His goal is to achieve the average score of M points or above on the N subjects print the minimum number of points Abhishek needs on the final subject to achieve the goal if the goal is unreachable , print -1 instead?
Answer» I am not GOOD in MATHS SORRY I can't TELL