# include <fstream>
# include <cstring>
using namespace std;
int main(void){
ifstream f("cifra.in");
ofstream f1("cifra.out");
int t,i,j,c,c1,uc;
int impar[9]={1,6,3,6,5,6,7,4,9};
int impar1[9]={1,7,0,6,1,7,1,0};
int par[9]={1,4,7,6,5,6,3,6,9};
int par1[9]={1,5,2,8,3,9,2,8,7};
char a[105];
f>>t;
for(j=1;j<=t;j++){
f>>(a+1);
a[0]='0';
int n=strlen(a);
c=(int)a[n-2]-48;
c1=(int)a[n-1]-48;
uc=0;
if((c+1)%2==0)
uc+=impar1[c1-1];
else
uc+=par1[c1-1];
uc+=c*7;
f1<<uc%10<<" "<<endl;
}
f.close();
f1.close();
return 0;
}