Problem Description

Create a program that reads a HTML file and verifies that for every start tag there is an end tag and that they are properly nested. Report any anomalies. Also report the number of of each tag. (Print the tag count statistics sorted by tag name.)

An example of a pair of tags is, the start tag "<p>" has an end tag "</p>".

it is important to note that some tags do not have an end tag. For example, "<img ...... />".

Things to Think About

• start and end tags may be on different lines or the same line


• one error that can occur is there is no end tag for a start tag
  or there is no start tag for an end tag


• do not expect web browsers to show nesting errors, many of them ignore or
  automatically fix nesting errors. that is why you need programs like this.

Example of properly nested tags

Note: indentation is not required. It is there to show nesting.

<h1>.....</h1>
   <img ..../>
   <p>
      <b>......</b>  
   </p>
   <div>
      <div>
         <p>
         </p>
      </div>
   </div>

Example of tags that are not properly nested

Note: indentation is not required. It is there to show nesting.

<h1>.....</h1>
   <p>
      <b>...... 
   </p>
      </b>                 <--- wrong nesting
   <p>                     <--- no end tag
   <div>
      <p>
      <div>
         </p>              <--- wrong nesting
      </div>
   </div>