#include<iostream>
#include<fstream>
#include<string>
using namespace std;

int A[10][2]={{0,0},{1,1},{4,6},{7,3},{6,6},{5,5},{6,6},{3,7},{6,4},{9,9}};

int main()
{ifstream f("cifra.in",ios::in);
ofstream g("cifra.out",ios::out);
int i,nr;
int T;
string N;
f>>T;

int s;
for(i=1;i<=T;i++)
	{s=0;
	f>>N;
	if(N.length()>=2)
		nr=int(*N.rbegin())-48+(int(*(N.rbegin()+1)-48))*10;
	else nr = int(N[0])-48;
	s+=((nr/20)*4 )%10;

	for(int j=0;j<=nr%20;j++)
			s+=A[j%10][(j/20)%2];
	g<<s%10<<'\n';
	}

f.close();
g.close();
return 0;
}