# include <fstream>
# include <cstring>
using namespace std;
int main(void){
    ifstream f("cifra.in");
    ofstream f1("cifra.out");
	int t,i,j,c,c1,uc;
	int impar[9]={1,6,3,6,5,6,7,4,9};
	int par[9]={1,4,7,6,5,6,3,6,9};
	char a[105];
	f>>t;
	for(j=1;j<=t;j++){
		f>>(a+1);
		a[0]='0';
		int n=strlen(a);
		c=(int)a[n-2]-48;
		c1=(int)a[n-1]-48;
		uc=0;
	    if((c+1)%2==0)
			for(i=0;i<c1;i++)
				uc+=impar[i];
		else
			for(i=0;i<c1;i++)
				uc+=par[i];
		uc+=c*7;
		f1<<uc%10<<" "<<'\n';
	}
	f.close();
	f1.close();
    return 0;
}