#include <bits/stdc++.h>
using namespace std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");

int a[202],na,r,S10,T,z;
char s[202];

int u(int c)
{
    int b=c%10,r=c%4,p=1;
    if(r==0)
    {
        r=4;
    }

    for(int i=1; i<=r; i++)
    {
        p*=b;

    }

    return p%10;
}

int suma(int k)
{
    int s=0;
    for(int i=1; i<=k; i++)
    {
        s=s+u(i);
    }

    return s%10;
}

int main()
{
    fin>>T;
    for(int t=1; t<=T; t++)
    {
        fin>>s;
        na=strlen(s);

        if(na==1)
        {
            r=s[0]-'0';
            fout<<suma(r)<<'\n';

        }

       else if(na==2)
        {
            r=s[na-1]-'0'+(s[na-2]-'0')*10;
            fout<<suma(r)<<'\n';

        }

       else{ r=s[na-1]-'0'+(s[na-2]-'0')*10;
        z=s[na-3]-'0';

        S10=suma(100);

        fout<<((z*S10)+suma(r))%10<<'\n';}
    }



    return 0;
}