#include<fstream>
using namespace std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");
int v[30005];
char s[111];
void determina()
{
    int i,j,r;
    for(i=1;i<=20;i++)
    {
        r=i%4;
        if(r==0)
            r=4;
        v[i]=1;
        for(j=1;j<=r;j++)
            v[i]*=(i%10);
        v[i]+=v[i-1];
        v[i]%=10;
    }
}

int main()
{
    int n,j,i,x;
    determina();
    fin>>n;

    for(j=1;j<=n;j++)
    {
        fin>>s;
        for(i=0;s[i];i++);
        i--;
        if(i==0)
            x=s[0]-'0';
        else
            x=(s[i-1]-'0')*10+(s[i]-'0');
        fout<<((x/20)*4+v[x%20])%10<<"\n";
    }
    return 0;
}