Question

Is

while (k >= 0 && arr[k] > 0) 

safe?

It loop when k in range and arr[k] > 0. But I don’t know if this is a good practice of coding. I know that if we do this

while (arr[k] > 0 && k >= 0) 

it would be a disaster.

Answer 1

It is safe in the fact that && short circuits. If k is less than zero, it won’t index into arr with it.

It might not be safe in that the body of your while loop might not decrement k correctly, leading to an infinite loop. Or it might not be safe if k is beyond arr‘s bounds.