# include <fstream>
using namespace std;
int calcul (int k)
{
    int r;
    r=k%4;
    if (k%10==2)
    {
        if (r==2)return 4;
        else return 6;
    }
    if (k%10==3)
    {
        if (r==1)return 3;
        else return 7;
    }
    if (k%10==7)
    {
        if (r==1)return 7;
        else return 3;
    }
    if (k%10==8)
    {
        if (r==2)return 4;
        else return 6;
    }
}                    
    
int main ()
{
    int m=100, i, x[]={0, 1, -1, -1, 6, 5, 6, -1, -1, 9}, s=0, v[105];
    ofstream fout ("cifra.out");
    for (i=1;i<=m;i++)
        if (x[i%10]>=0)
        {
           s=(s+(x[i%10])%10)%10;    
           v[i]=s;
        }    
        else
        {
           s=(s+(calcul(i))%10)%10;
           v[i]=s;
       }    
    int t, z, j;
    char ss[105];       
    ifstream fin ("cifra.in");
    fin>>t;
    fin.get();
    for (i=1;i<=t;i++)
    {
        z=0;
        fin.getline(ss, 101);
        j=strlen(ss)-1;
        if (j>0) z=ss[j-1]-'0';
        z=z*10+(ss[j]-'0');
        fout<<v[z]<<endl;
    }    
    return 0;
}