#include<stdio.h>
#include<stdlib.h>
#include<string.h>

int main(void){
  FILE *f, *g;
  f = fopen("cifra.in", "r");
  g = fopen("cifra.out", "w");
  int t;
  fscanf(f, "%d\n", &t);
  char n[10000];
  int pow20[20] = {1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0};
  int sum20 = 4;
  int last =0;
  int dec =-1;
  int sum=0;
  while(t--) {
    last=0;
    dec=0;
    sum=0;
    fscanf(f,"%s", &n);
    last = n[strlen(n)-1] - '0';
    if (strlen(n) > 1) dec = n[strlen(n)-2] - '0';
    //fprintf(g,"%s %d %d", n, last, dec);
    int i;
    int pad =0;
    if (dec>0 && dec%2!=0) pad=1;
    for(i=0;i<last+pad*10;i++) {
      sum+=pow20[i];
    }
    if (dec>0) {
    	sum = (sum+ (dec / 2)*4) % 10;
    }
    else sum = sum%10;
    fprintf(g,"%d\n", sum);
  }
}