#include<stdio.h>
char*a[]={"","23456789012","26262626262","29292929292","28406284062","27272727272",
"28406284062","25252525252","28282828282","21098765432"},b[110]="0";
t,n,s,i;
main(){freopen("cifra.in","r",stdin);freopen("cifra.out","w",stdout);
scanf("%d\n",&t);
for(;t--;){gets(b+1);n=atoi(b+strlen(b)-2);s=0;
for(i=10;--i;)s+=a[i][n/10+(n%10>=i)];
printf("%d\n",s%10);}
}