#include <fstream>
#include <cstring>

using namespace std;

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