title: If the numbers from 1 to 4321 were written out, how many times would the digit '5' appear?
body: <p>I have figured out the answer for this program, however I don't really understand what does backslush means in here.</p>
  
  <p>I tried to remove the backslush, then the program print all of numbers from 1 to 4321, but it did not grep how many times number 5 appear.</p>
  
  <p>When I put backslush, it just show the number how many time number 5 appear.</p>
  
  <p>here is my code:</p>
  
  <pre><code>#!/bin/bash
  seq 4321 | \
  while read -n1 digit; do
   echo $digit
  done | grep -c 5
  </code></pre>