#include <bits/stdc++.h>
using namespace std;
ifstream in("cifra.in");
ofstream out("cifra.out");
typedef unsigned long long ll;
ll rl(ll a,ll b){
	int r=1;
	while(b){
		if(b % 2==1)r=(r*a)%10;
		a=(a*a)%10;
		b/=2;
	}
	return r;
}

ll ans[109],f;
int main(){
for(ll i=1;i<=100;i++)
ans[i]=(ans[i-1]+rl(i,i))%10;
int t,si;
in >>t;
while(t--){
	string s;
	in >>s;
	si=s.length();
	f=0;
	for(ll i=max(0,si-2);i<=si-1;++i){
		f=f*10+s[i]-'0';
	}
	out <<ans[f]<<"\n";
}
return 0;
}