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

int main(){
    int t;
    cin>>t;
    while(t--){
        ll n;
        cin>>n;
        if(n==0) n = 1;
        int ans = 0;
        int now = n % 10;
        n--;
        while(now!=0){
            ans += now;
            ans %= 10;
            int nxt = n % 10;
            now *= nxt;
            n--;
        }
        ans++;
        ans%=10;
        cout<<ans<<endl;
    }
}