Maximum subarrays problem using the cumaltive sum

#1

I don’t understand the code mention in video.
first we store the cumsum[0] = a[0], that means the first value is goint to store in the cumsum first index. But the arrays elements is readed by 1 <n, so it means that the array a will store the value from to 1 < n, then how a[0] index is readed to store in the cumsum at first postition

#2

Hey @Vikaspal Let me describe how we are making the cumsum array.
Now both the arrays are indexed 0 based.
The statement we are using to build the cum sum array is:-
if(i==0) cumsum[i]=A[i];
else cumsum[i]=cumsum[i-1]+A[i];
We are considering the case for 0 separately because there is no position referring to cumsum[-1] and it will throw segmentation fault.
So cumsum[i] does store the value of sum of all elements upto index i in the original array but because we are using 0 based indexing , we can also say that cumsum[i] is storing the sum of first i+1 elements in the original array, so cumsum[n-1] stores the sum of n elements.

#3

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