#include <bits/stdc++.h>   using namespace std;   double power(float x, int y) {     float temp;     if (y == 0) return 1;     temp = power(x, y / 2);     if (y % 2 == 0)       return temp * temp;     else {       if (y > 0)         return x * temp * temp;       else         return (temp * temp) / x;     }   }   bool isPrime(int n) {     if (n <= 1) return false;     if (n <= 3) return true;     if (n % 2 == 0 || n % 3 == 0) return false;     for (int i = 5; i * i <= n; i = i + 6)       if (n % i == 0 || n % (i + 2) == 0) return false;     return true;   }   void solve() {     long long int n;     cin >> n;     vector<long long int> a(n);     for (long long int i = 0; i < n; i++) cin >> a[i];     ;     long long int ans = a[0];     long long int t = a[0];     for (long long int i = 1; i < n; i++) {       t += a[i];       ans = min(ans, t);     }     cout << abs(ans) << endl;   }   int main() {     long long int t;     cin >> t;     while (t--) solve();   }   