#include <stdio.h>
#include <string.h>
#define fr(i,a,b) for(int i=a;i<b;++i)
#define ll long long
int a[10]={0,1,5,2,8,3,9,2,8,7};
int b[10]={0,1,7,0,6,1,7,4,8,7};
char str[101];
int main(){
    freopen("cifra.in","r",stdin);
    freopen("cifra.out","w",stdout);
    int t;
    scanf("%i\n",&t);
    fr(i,0,t){
        scanf("%s",str);
        int len=strlen(str);
        char c1='0';
        if(len>1) c1=str[len-2];
        char c2='0';
        if(len) c2=str[len-1];
        int s=(c1-'0')*7;
        if((c1-'0')%2) s+=b[c2-'0'];
        else s+=a[c2-'0'];
        s=s%10;
        printf("%i\n",s);
        }
    return 0;
    }