#include <iostream>
#include <cstdio>

using namespace::std;

int t, n;

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