#include<fstream.h>
 #include<string.h>
  ifstream f("cifra.in");
   ofstream g("cifra.out");
    int main(){
		char a[103];
		int n,i,nr,l,v[10];
		v[0]=0;
        v[1]=1;
        v[2]=5;
        v[3]=2;
        v[4]=8;
        v[5]=3;
        v[6]=9;
        v[7]=2;
        v[8]=8;
        v[9]=7;
		f>>n;
		for(i=1;i<=n;i++){
		    f>>a;
			nr=0;
			l=strlen(a);
			//g<<l<<"\n";
			if(l-2>=0)
				nr=(7*(a[l-2]-'0'))%10;
			g<<(nr+v[a[l-1]-'0'])%10<<"\n";
		}
		g.close();
		return 0;
	}