#include <fstream>
#include <cstring>
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;
}
void bulid(){
    for(int i=1;i<=100;i++){
        v[i]=(v[i-1]+lgput(i))%10;
    }


}
int main(){
    bulid();
    fin>>t;
    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;
}