Can someone explain me this codes , please

Question

https://code.sololearn.com/c3Nw01gXV3fd/?ref=app
https://code.sololearn.com/c3zP2pdN7Lmt/?ref=app
https://code.sololearn.com/c1w4yy1rlxRm/?ref=app

Answer 1

In
https://code.sololearn.com/c3zP2pdN7Lmt/?ref=app

if you replace (1/2) with 0.5 then it works

Answer 2

Maybe it's better to have separate questions for the different codes?

Answer 3

Thanks Vedang

Answer 4

U can answer in comments