title: How to finding the same character in two string with python
body: <p>I need to finding the same character in two string.<br/>
  One from open file, i get it using this and one from user input<br/> 
  Example :</p>
  
  <p><pre>
  x = raw_input('input x')</p>
  
  <code>y = open('file.txt' , 'r')
  y = y.read()
  </code></pre>
  
  <p></p>
  
  <p>Assume we get the x = abcde and y = Compare<br/>
  I need to find a situations where x == y<br/>
  In the example first i need to find 'a' in y , and then 'b' , and etc,<br/>
  I dont need to find all string that same, only sequentially from the first till last.<br/>
  From my example we can guess that after 'a' there will be no 'b' in the y,<br/>
  So its okay, i dont need to find the 'e' as in y have 'e'. <br/></p>