#include<iostream>
#include<cstring>
#include<cstdio>
#include<string>
using namespace std;
int main(){
    int T,maxi,n,a;
    scanf("%d",&T);
    while (T--){
        scanf("%d",&n);
        maxi = 0;
        for (int i = 1;i <= n; ++i){
        scanf("%d",&a);
        maxi = max(maxi,a);}
        printf("%d\n",maxi);
    }
    return 0;
}