#include<iostream>
#include<algorithm>
#include<cstring>
#include<cstdio>
using namespace std;
int main()
{
    int T,n;
    ///freopen("in.txt","r",stdin);
    scanf("%d",&T);
    while(T--){
        int a,ans = 0;
        scanf("%d",&n);
        for(int i = 0;i<n;i++){
            scanf("%d",&a);
            ans = max(a,ans);
        }
        printf("%d\n",ans);
    }
    return 0;
}