#include <fstream>
#include <string.h>
#include <math.h>

using namespace std;

/*int main()
{
    ifstream f;
    f.open("cifra.in");
    ofstream g;
    g.open("cifra.out");
    int a[100];
    int i;
    a[0]=0;
    for (i=1; i<100; i++)
    {
        a[i]=pow(i%10,i%4+4);
        a[i]=(a[i]+a[i-1])%10;
    }

    char s[101];
    int n,nr;
    f >> n;
    for (i=0; i<n; i++)
    {

        f >> s;
        int l=strlen(s);
        if (l==1) g << a[s[0]-'0'] << endl;
        else
        {
            nr=(s[l-1]-'0')+10*(s[l-2]-'0');
            g << a[nr] << endl;
        }
    }
    f.close();
    g.close();
}*/

int main ()
{
	 char string[101];
	 long j, a, T, b;
	 int v[101];
	 ifstream ins;
	 ins.open("cifra.in");
	 ins>>T;
	 ofstream ous;
	 ous.open("cifra.out");
	 v[0]=0;
	 for (j=1; j<=99; j++)
	 {
		b=pow (j%10, j%4+4);
		b=b%10;
		v[j]=(v[j-1]+b)%10;
	 }
	 for (j=0; j<T; j++)
	 {
		ins>>string;
		a=strlen (string);
		if (a==1)
		{
			ous<<v[string[0]-'0']<<"\n";
		}
		else
		{
			b=((long)(string[a-1]-'0'))+10*((long)(string[a-2]-'0'));
			ous<<v[b]<<"\n";
		}

	 }
	 ins.close();
	 ous.close();
	 return 0;
}