Sum of the updated array after performing the given operation | C ++ implementation of the approach ; Utility function to return the sum of the array ; Function to return the sum of the modified array ; Subtract the subarray sum ; Sum of subarray arr [ i ... n - 1 ] ; Return the sum of the modified array ; Driver code
#include <iostream> NEW_LINE using namespace std ; int sumArr ( int arr [ ] , int n ) { int sum = 0 ; for ( int i = 0 ; i < n ; i ++ ) sum += arr [ i ] ; return sum ; } int sumModArr ( int arr [ ] , int n ) { int subSum = arr [ n - 1 ] ; for ( int i = n - 2 ; i >= 0 ; i -- ) { int curr = arr [ i ] ; arr [ i ] -= subSum ; subSum += curr ; } return sumArr ( arr , n ) ; } int main ( ) { int arr [ ] = { 40 , 25 , 12 , 10 } ; int n = sizeof ( arr ) / sizeof ( arr [ 0 ] ) ; cout << sumModArr ( arr , n ) ; return 0 ; }