#include<fstream>
#define IN "cifra.in"
#define OUT "cifra.out"
#define MAX 99
#include<string.h>
#define MAX_SIR 101
 
using namespace std;
 
ifstream in(IN);
ofstream out(OUT);
 
int a[MAX], TEST, N, s, l, c1, c2;
char numar[MAX_SIR];
 
int main()
{
    a[0]=0;
    for(int i=1; i<=MAX; i++)
    {
        s=1;
        for(int j=0; j<i; j++)
            s=s*i%10;
        a[i]=(a[i-1]+s)%10;
    }
    in>>TEST;
    in.getline(numar, MAX_SIR);
    while(TEST)
    {
        in.getline(numar, MAX_SIR);
        l=strlen(numar);
        c2=numar[l-1]-'0';
        c1=0;
        if(l>1)
            c1=numar[l-2]-'0';
        out<<a[c1*10+c2]<<'\n';
        --TEST;
    }
    in.close();
    out.close();
    return 0;
}