#include <stdio.h>
#include <cstring>
using namespace std;
char s[102],a,b,c;
char sum[20]={1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0};
int t,i,n,j,rez;
int main()
{
    freopen("cifra.in","r",stdin);
    freopen("cifra.out","w",stdout);
    scanf("%d%c",&t,&s[0]);
    for(i=1;i<=t;i++){
        a=b=rez=0;
        fgets(s, 102, stdin);
        n = strlen(s);
        if(n>=3)
        a=s[n-3]-'0';
        b=s[n-2]-'0';
        c=a*10+b;
        rez=c/20*4;
        for(j=0;j<c%20;j++)
            rez+=sum[j];
        printf("%d\n",rez%10);
    }
    return 0;
}