#include <bits/stdc++.h> 
using namespace std; 
int maxSum(int arr[], int n, int k) 
{ 
    int max_sum = INT_MIN;  
    for (int i = 0; i < n - k + 1; i++) { 
        int current_sum = 0; 
        for (int j = 0; j < k; j++) 
            current_sum = current_sum + arr[i + j];  
        max_sum = max(current_sum, max_sum); 
    } 
  
    return max_sum; 
}  
int main() 
{ 
    int arr[] = { 1, 4, 2, 10, 2, 3, 1, 0, 20 }; 
    int k = 4; 
    int n = sizeof(arr) / sizeof(arr[0]); 
    cout << maxSum(arr, n, k); 
    return 0; 
} 
