#include <fstream>

using namespace std;
ifstream f1("cifra.in");
ofstream f2("cifra.out");
char c[105];
short int s[105],t,n,i,j,b,l;
void sum(){
    int a;
    for(i=1;i<=100;i++)
    {
        a=1;
        for(j=1;j<=i;j++){
            a=(a*i)%10;
            }
        s[i] = (s[i-1]+a)%10;
    }
}
void read(){
    f1>>(c+1);
    b=0;i=1;c[0]='0';
    while(c[i]!=0){i++;}
    b=(c[i-2]-'0')*10+c[i-1]-'0';
}
void print(){
    f2<<s[b]<<"\n";
}


int main(){
    f1>>t;
    sum();
    for(l=1;l<=t;l++){
        read();
        print();
    }
f1.close();
f2.close();
}