A

# include<iostream>
using namespace std;
# define ll long long

const int N=52;
int t,n;
ll a[N],ans;

void solve(){
	cin>>n;
	ans=0;a[n]=-1;
	for(int i=0;i<n;++i) cin>>a[i];
	for(int i=n;i>=0;--i)
		if(a[i]<0){
			ans-=a[i];
			for(int j=0;j<i;++j) a[j]+=a[i];
			a[i]=0;
		}
	cout<<ans<<endl;
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	cin>>t;
	while(t--) solve();
	return 0;
}