#include <iostream>
#include <fstream>
#include <cstring>

#define ENDL '\n'

using namespace std;

ifstream f("cifra.in");
ofstream g("cifra.out");

int main()
{
    int N,v[101]={0};
    char s[101];
    f>>N;

    for(int i=1;i<=99;i++)
    {
        v[i]=i;
        for(int j=1;j<i;j++)
        {
            v[i]*=i;
            v[i]%=10;
        }
        v[i]+=v[i-1];
        v[i]%=10;
    }

    for(;N--;)
    {
        f>>s;
        int l=strlen(s);
        if(l==1) g<<v[ s[l-1] - '0']<<ENDL;
        else g<<v[ (s[l-2]-'0')*10+s[l-1]-'0' ]<<ENDL;
    }
    return 0;
}