title: How to delete chars from string until first char is a letter?
body: <p>I have a program which works with strings (Pascal). After reading a string if the first char is not a letter then I need to delete all first characters until the first is a letter. I have tried to write it several times, but always it deletes all string or nothing.</p>
  
  <p>If program reads "123%^&amp;abc" then result should be "abc"
  In ASCII table letters are from 65..90 and from 97..122</p>
  
  <p>This is how far I am:</p>
  
  <pre><code>variables    a: set of 65..90;
               b: set of 97..122;
  -------------------
    bool:=false;
    While (bool=false) do
    begin
      Writeln(s[1]);
      If (Ord(s[1]) in a) or (Ord(s[1]) in b) then
      begin
      bool:=true;
      end else
      delete(s,1,1);
    end;
  </code></pre>
  
  <p>I don't understand why it does not work?
  Can you help me with this little procedure? Thank you.</p>