Q2. The following algorithm returns the product of two numbers, a and b. The parameters x and y are natural numbers. First, prove the correctness of the algorithm. Then, analyze the time complexity of the algorithm in the worst case scenario. function mult(a, b) if b = 0 : return 0 else if bis odd: return (mult (2a, b/2 ) +a) else: return (mult(2a, b/2))