Hi experts,

I have many occurances of the following headers in a file. I need to grep for the word changed/inserted in the header, calculate the difference between the two numbers and list the count incrementally.
Headers in a file look like this:
----------[changed to 229-232]---------
-----------[inserted 294-296]----------
------------[changed to 861]-----------

I should grep for the word changed, also grep the numbers listed 229 and 232 and find their difference. The difference in the number of lines is the output. Similarly grep for inserted and the difference in the numbers. If the header contains just one number increment by one.
Output should be like:
Number of lines changed :4 (here 3 from first header and one from last header matching the word changed)
Number of lines inserted :2

Please help me, i am held up with this for long.