#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<cstdlib>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<stack>

using namespace std;

int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    int tt;
    scanf("%d",&tt);
    while (tt--)
    {
        int n;
        scanf("%d",&n);
        int maxx=-1;
        for (int i=1; i<=n; i++)
        {
            int x;
            scanf("%d",&x);
            maxx=max(maxx,x);
        }
        printf("%d\n",maxx);
    }
    return 0;
}