//#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<map>
#include<cmath>
#include<queue>
#include<stack>
#include<ctime>
#include<vector>
#include<set>
#include<cfloat>
#include<sstream>

using namespace std;

//const int maxn=1250;
//const long long INF=999999999999999;
const int INF=999999999;
//const float eps = 0.00000001;
//const int mod=1000000007;
const int mod=9973;
//const long long mod=100000000000000;
//const int VM=15;
const int VM=100210;
const int EM=500010;
//const int N=120;
//const double PI=3.14159;
//const double PI=3.14159265359;
const double PI=acos(-1.0);     //圆周率PI
const double eps=1e-10;
//const int N=1e6+200;
//const int N=20;

typedef pair<int,int> P;
//int dir[4][2]={{-1,0},{1,0},{0,-1},{0,1}};
//int dir[4][2]={{0,1},{0,-1},{-1,0},{1,0}};
int dir[4][2]={{1,0},{0,-1},{-1,0},{0,1}};
#define L(x) (x<<1)
#define R(x) (x<<1|1)

/**


*/

int a[50];

int main(){

    //freopen("input.txt","r",stdin);

    int t,n;
    scanf("%d",&t);
    while(t--){
        scanf("%d",&n);
        int x,maxx=0;
        for(int i=0;i<n;i++){
            scanf("%d",&x);
            if(maxx<x)
                maxx=x;
        }
        printf("%d\n",maxx);
    }

    return 0;
}