Develop a Stack abstract data type 

 

The Stack class should include the following methods: 

• push(item) function to add a new item to the stack
• pop() function to remove the top item from the stack
• peek() to return the top item in the stack
• is_empty() to test whether the stack is empty
• size() to tell the size (number of items) in the stack

Develop a html_checker function

 

The function: 

• Takes a string of HTML code as argument;
• Returns true if all tags are balanced; false if otherwise.

 

Here is what the function should do: 

 

• Develop a new Stack object;
• Use the split() method of a string to split it into text lines;
• Develop a loop to read the text lines, and for each text line:
  • If the text line matches an opening tag (e.g.

    ), add the tag name (e.g. "h1") to the stack;

  • If the text line is ordinary content without a HTML tag, skip the line;
  • If the text line is a closing tag (e.g. ), check whether the stack is empty():
    • The HTML code is unbalanced if stack is currently empty;
    • If not empty, use pop() to read and remove the top item from stack:
      • The top item/tag matches the current closing tag, then the HTML code is balanced (true);
      • Otherwise, the HTML code is unbalanced (false).

Program Execution 

 

Develop two variables, one with balanced HTML code and the other with unbalanced HTML code. Run the html_checker function with each of the two variables as argument to test the program.