Maximum sum

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int N = 2e5+1;
ll X[N], A[N];

int main() {
	int n;
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> X[i];
	}
	A[0] = max(X[0],0ll);
	ll ans = A[0];
	for (int i = 1; i < n; ++i) {
		A[i] = max(A[i-1] + X[i], X[i]);
		ans = max(ans, A[i]);
	}
	cout << ans << '\n';
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER

Test 14

Verdict: WRONG ANSWER

Test 15

Verdict: WRONG ANSWER