Returning index instead of boolean when knuth_morris_pratt matches.

[amirsoroush]

In knuth morris pratt algorithm, I think it's better to return the "index" of the matched substring in case of success, and -1 in case of failure, so that it would be consistent with the str.find() in Python. True and False aren't that helpful.

[ArhamaQ]

Hey, My name is Arhama. I am a beginner in open source contribution. After exploring a couple of hours, this is the first project I have found for myself. and I think i can work on this please assign me this work

[Rathish-Rajendran]

Hi, I've been following the project closely and I'm keen to tackle this specific issue. With my experience in python, I'm confident I can provide a valuable solution. Please consider assigning this issue to me. Thanks!