#include<bits/stdc++.h>
using namespace std;
int t;
int main(){
	cin>>t;
	while(t--){
		int n,a[114514]={},MAX=-0x7ffffff;
		cin>>n;
		for(int i=1;i<=n;i++){
			cin>>a[i];
			if(a[i]>MAX)MAX=a[i];
		}
		cout<<MAX<<"\n";
	}
	
	return 0;
}

为啥RE