*** It's not necessarily that this problem is overly difficult but I was just wondering if anyone could help show the clear and correct way to solve this by use of a loop invariant and induction.***
*Use induction to prove the following program to compute x*y is correct given the initial assertion that x is a non-negative integer and the final asseration that the value returned from mult(x,y) is x*y.
if(x==0) then return 0
else return y + mult(x-1, y)