#include <bits/stdc++.h>

using namespace std;

const int maxn = 60007;
int a[maxn];
int dp[maxn];

int main() {
    int n;
    cin >> n;
    for (int i = 1; i <= n; ++i)
        cin >> a[i];

    dp[0] = 0;
    for (int i = 1; i <= n; ++i)
        dp[i] = max(dp[i - 1] + a[i],  max(0,a[i]));

    int ans = *max_element(dp, dp + n);
    cout << ans;
    system("pause");
    return 0;

}

max(0, a[i]). This is wrong!
You must get sum of consecutive elements.

Edited by author 07.11.2018 20:19

Try follow:
3
-1
-1
2