Watermelon codechef lunchtime Problem solution with explanation| September Lunchtime-
2 1 -1 2 1 2
Watermelon CodeChef lunchtime Problem solution->
You may perform any number of operations on this sequence (including zero).
means you we can subtract i any number of time.
but we know that we will always have i=1 that is first index and every number is multiple of 1 so we can generate 0 by subtracting 1 any number of times so the conclusion is if the sum is grater then 0 ans is always "YES" because we can generate 0 by subtracting 1 any number of time.
here we need a little observation for this question.
complete code of the problem