#include<iostream>
#include<fstream>
#include<string>
#include<math.h>

using namespace std;

const int ult=4;

int A[11][4]={0,0,0,0,
			1,1,1,1,
			2,4,8,6,
			3,9,7,1,
			4,6,4,6,
			5,5,5,5,
			6,6,6,6,
			7,9,3,1,
			8,4,2,6,
			9,1,9,1};


int main()
{ifstream f("cifra.in",ios::in);
ofstream g("cifra.out",ios::out);

int T;
int i,k,l,m,s=0;
char j;
string B;
f>>T;

for(i=1;i<=T;i++)
{s=0;
f>>B;
if(B.size()<3)
{k=B[0]-48;
if(B.size()==2)
	k=k+(int(B[1])-48)*10;}
else(k=int(B[B.size()-1])-48+(int(B[B.size()-2])-48)*10);

for(l=0;l<=k;l++)
{m=l%10;
s=s+A[m][(l+3)%4];
}
s=s%10;
g<<s<<endl;
}

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