#include<stdio.h>
FILE *f1,*f2;
int main()
{unsigned t,i; unsigned char c;short unsigned uc1,zc,uc;
f1=fopen("cifra.in","r");
f2=fopen("cifra.out","w");
fscanf(f1,"%u\n",&t);
for(i=0;i<t;i++){
zc=uc=0;
do{
c=fgetc(f1);
if(c!='\n'){zc=uc;
uc=c-48;}
}while(c!='\n');
uc1=zc*7%10;
if(zc%2==0)
{uc1=uc1+1*(uc>=1)+4*(uc>=2)+7*(uc>=3)+6*(uc>=4);
uc1=uc1+5*(uc>=5)+6*(uc>=6)+3*(uc>=7)+6*(uc>=8)+9*(uc>=9);}
else
{uc1=uc1+1*(uc>=1)+6*(uc>=2)+3*(uc>=3)+6*(uc>=4);
uc1=uc1+5*(uc>=5)+6*(uc>=6)+7*(uc>=7)+4*(uc>=8)+9*(uc>=9);}
uc=uc1%10;
fprintf(f2,"%u\n",uc);
}
fclose(f1);fclose(f2);
return 0;
}