Vlookup / Countif Combination

Hello, I am trying to apply a vlookup / countif combination on a simple dataset.

I have several consecutive zones of varying lengths. Some actions have been applied on subsections within these zones therefore I want to count how much has been completed.

For example;

Zone 1: 50 to 65, Action 1 was completed between 60 and 70, therefore the count is 5.

Please see attached worksheet with manually completed desired output.

As always your help is much appreciated.

Thanks.