PLEASE WRITE IN C++

3) Consider the following recursive function:

int p( int x)

{

if (x =< 3)

return x;

else

return p(x-1) * p(x-3);

} // end p

Let m (x) be the number of multiplication operations that the execution of p(x) performs.

a. Write a recursive definition of m (x).

b. Prove that your answer to part a is correct by using mathematical induction.