Two recursive calls in a Merge Sort function confusion

Question

I have been out of touch with Algorithms for a while and have start revising my concepts these days. To my surprise the last i remember of my recursions skill was that i was goo

Answer 1

Just follow the execution...

First call 0,7 --> enters if, middle = 3 (integer division), calls again as (0,3)
Second call 0,3 --> enters if, middle = 1, calls again as (0,1)
Third call 0,1 --> enters if, middle = 0, calls again as (0,0)
Fourth call 0,0 --> does not enter if, back to third call
Third call 0,1 --> calls as middle+1,high which is (1,1)
Fifth call 1,1 --> does not enter if, back to third call
Third call 0,1 --> calls the string you didn't expect

can continue on but that is where the string you aren't expecting is executed.