Question

(Python 3.5, short and simple codes please)

Two non-negative integers x and y are equal if either:

• Both are 0, or
• x-1 and y-1 are equal

Write a function named equals that recursively determines whether two parameters (both containing integer values) are equal and returns True or False.

Answer 1

def equals(x, y):
    if x == 0:
        return y == 0
    elif y == 0:
        return x == 0
    else:
        return equals(x - 1, y - 1)