#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
 
int maxSubarraySum(const vector<int>& b) {
    int n = b.size() - 1; // Adjust for 1-based indexing
    if (n == 0) return 0;
 
    int T = 0; // Initialize T to 0, which will store the maximum sum subarray
    int prv = 0; // Initialize prv to 0, which will store the current maximum sum subarray ending at b[i]
 
    for (int i = 1; i <= n; ++i) {
        int current = max(prv + b[i], b[i]);
        current = max(current, 0);
        prv = current;
        T = max(T, current);
    }
 
    return T;
}
 
int main() {
    int n;
    cin >> n;
 
    vector<int> b(n + 1); // Adjust for 1-based indexing
    for (int i = 1; i <= n; ++i) {
        cin >> b[i];
    }
 
    int result = maxSubarraySum(b);
    cout << "Maximum subarray sum is " << result << endl;
 
    return 0;
}
 

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