#include <bits/stdc++.h>

using namespace std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");

int n,i,t,v[105];
char a[105];

int lgput(int n) {
    int s=1,p=n;
    while (p!=0) {
        if(p%2==1)
            s=(s*n)%10;
        n=(n*n)%10;
        p/=2;
    }
    return s;
}
int main(){
    fin>>t;
    for(i=1;i<=100;i++)
        v[i]=(v[i-1]+lgput(i))%10;
    while (t--) {
        fin>>a+1;
        n=strlen(a+1);
        if(n==1)
            fout<<v[a[n]-'0']<<"\n";
        else
            fout<<v[a[n]-'0'+(a[n-1]-'0')*10]<<"\n";
    }
    return 0;
}