#include<fstream>

using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");

int c2(int k){
    if(k%4==0) return 6;
    if(k%4==1) return 2;
    if(k%4==2) return 4;
    if(k%4==3) return 8;
}
int c3(int k){
    if(k%4==0) return 1;
    if(k%4==1) return 3;
    if(k%4==2) return 9;
    if(k%4==3) return 7;
}
int c4(int k){
    if(k%2==0) return 6;
    else return 4;
}
int c7(int k){
    if(k%4==0) return 1;
    if(k%4==1) return 7;
    if(k%4==2) return 9;
    if(k%4==3) return 3;
}
int c8(int k){
    if(k%4==0) return 6;
    if(k%4==1) return 8;
    if(k%4==2) return 4;
    if(k%4==3) return 2;
}
int c9(int k){
    if(k%2==0) return 1;
    else return 9;
}

int main(){
    int T,n;
    f>>T;
    for(int j=1;j<=T;j++){
        f>>n;
        int s=0;
        for(int i=1;i<=n;i++){
            int u=i%10;
            if(u==1) s=s+1;
            if(u==2) s=s+c2(i);
            if(u==3) s=s+c3(i);
            if(u==4) s=s+c4(i);
            if(u==5) s=s+5;
            if(u==6) s=s+6;
            if(u==7) s=s+c7(i);
            if(u==8) s=s+c8(i);
            if(u==9) s=s+c9(i);
        }
        g<<s%10<<endl;
    }
}