#include<bits/stdc++.h>
using namespace std;
int t;
string n;
int a[100]={
0,1,5,2,8,3,9,2,8,7,7,8,4,7,3,8,4,1,5,4,
};
int b[100]={
0,1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,
0,1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,
0,1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,
0,1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,
0,1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9
};
int main(){
ifstream fin("cifra.in");
ofstream fout("cifra.out");
fin>>t;
for(int i=1;i<=t;i++){
fin>>n;
if(n.length()==1) fout<<a[int(n[n.length()-1]-48)]<<endl; else{
for(int i=1;i<=(int(n[n.length()-2]-48)*10+int(n[n.length()-1]-48));i++){
a[i]=(b[i]+a[i-1])%10;
}
fout<<a[int(n[n.length()-2]-48)*10+int(n[n.length()-1]-48)]<<endl;
}
}
return 0;
}