#include <fstream>
#include <cstring>

using namespace std;

ifstream f("cifra.in");
ofstream g("cifra.out");
long int t,ue[102],u,i,j,x,n;
char a[102];
int main()
{
    f>>t;
    for(i=1;i<=100;i++)
    {
        u=i;
    for(j=2;j<=i;j++)
        u=(u*i)%10;
    ue[i]=(ue[i-1]+u)%10;
    }
    for(i=1;i<=t;i++){
         f>>a;
        n=strlen(a);
        if(1<n)
            x=(a[n-2]-'0')*10+(a[n-1]-'0');
        else
            x=a[n-1]-'0';
         g<<ue[x]<<"\n";
    }
    return 0;
}