#include <cstdio>
#include <cstring>

using namespace std;

char v[150];
int c[105];

void suma(){
    int i,p,j;
    for(i = 1;i <= 100;i++){
        p = 1;
        for(j = 1;j <= i;j++){
            p = (p * i)%10;
        }
        c[i] = (c[i-1] + p)%10;
    }
}

void afiseaza(){
    int i,t,len,rez,j;
    scanf("%d",&t);
    for(i = 1;i <= t;i++){
        scanf("%s",&v);
        for(j = strlen(v);j > 0;j--){
            v[j] = v[j-1];
        }
        v[0] = '0';
        len = strlen(v+1);
        rez = (v[len-1] - '0')*10 + (v[len] - '0');
        printf("%d\n",c[rez]);
    }
}

int main(){
    int i;
    freopen("cifra.in", "r", stdin);
    freopen("cifra.out", "w", stdout);
    suma();
    afiseaza();
    return 0;
}