#!/usr/bin/env perl

use strict;
use warnings;

my $t = <>; chomp $t;
for (my $i = 0; $i < $t; $i++) {
  my $s = <>; chomp $s;
  my @vs = split//, $s;
  if (@vs == 1) {
    print $vs[0] . "\n";
    next;
  }
  for (;;) {
    my @nvs;
    for (my $i = 0; $i < @vs - 1; $i++) {
      my $num = $vs[$i] + $vs[$i + 1];
      $num = int($num / 10) + $num % 10 if $num >= 10;
      push @nvs, $num;
    }
    if (@nvs == 1) {
      print $nvs[0] . "\n";
      last;
    }
    @vs = @nvs;
  }
}