#include<fstream>
#include<iostream>
using namespace std;
long VAL[11][2];
long NR[10],i,j,suma,nr,T,n;
char N[102];
int main()
{
vAL[1][0]=1;
NR[1]=1;
VAL[0][0]=0;
NR[0]=0;
VAL[2][0]=4;
VAL[2][1]=2;
NR[2]=2;
VAL[3][0]=3;
VAL[3][1]=7;
NR[3]=2;
VAL[4][0]=6;
NR[4]=1;
VAL[5][0]=5;
NR[5]=1;
VAL[6][0]=6;
NR[6]=1;
VAL[7][0]=3;
VAL[7][1]=7;
NR[7]=2;
VAL[8][0]=6;
VAL[8][1]=4;
NR[8]=2;
VAL[9][0]=9;
NR[9]=1;
ifstream in("cifra.in");
ofstream out("cifra.out");
in>>T;
for(i=1;i<=T;i++)
{
in.getline(N,102);
nr=N[strlen(N)-2]-'0';
if(nr==0)
nr=(N[strlen(N)-1]-'0')*10;
else
nr=nr*10+N[strlen(N)-1]-'0';
suma=0;
suma=nr/20;
nr=nr%20;
for(j=1;j<=nr;j++)
{
suma+=VAL[j][j%NR[j]];
}
suma=suma%10;
out<<suma<<endl;
}
out.close();
in.close();
 
return 0;
}