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// C++ program for Implementing prefix sum array
#include <bits/stdc++.h>
using namespace std;
// Fills prefix sum array
void fillPrefixSum(int arr[], int n, int prefixSum[])
{
prefixSum[0] = arr[0];
// Adding present element with previous element
for (int i = 1; i < n; i++)
prefixSum[i] = prefixSum[i - 1] + arr[i];
}
// Driver Code
int main()
{
int arr[] = { 10, 4, 16, 20 };
int n = sizeof(arr) / sizeof(arr[0]);
int prefixSum[n];
fillPrefixSum(arr, n, prefixSum);
for (int i = 0; i < n; i++)
cout << prefixSum[i] << " ";
}
// This code is contributed by Aditya Kumar (adityakumar129)
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Input : arr[] = {10, 20, 10, 5, 15}
Output : prefixSum[] = {10, 30, 40, 45, 60}
Explanation : While traversing the array, update
the element by adding it with its previous element.
prefixSum[0] = 10,
prefixSum[1] = prefixSum[0] + arr[1] = 30,
prefixSum[2] = prefixSum[1] + arr[2] = 40 and so on.