#include <fstream>
#include <string>
using namespace std;
int c[]={1,4,7,6,
		5,6,3,6,9,
		0,1,2,3,6,
		9,6,7,4,9,0};
int s=0,n;
int main(){
	string number;	
	for(int i=0;i<20;i++)
		s+=c[i];
	ifstream in("cifra.in");
	ofstream out("cifra.out");
	in>>n;
	for(int i=0;i<n;i++){
		in>>number;
		int last = number[number.length()-1]-'0';
		if(number.length()>1)
			last+=(number[number.length()-2]-'0')*10;
		int ans=4*(last/20);
		for(int i=0;i<last%20;i++)
			ans+=c[i];
		ans=ans%10;
		out<< ans<<'\n';
	}
	return 0;
}