All these problems have to be solved using recursion. Also create a README.txt file which explains in 2-3 lines for each problem; how you have solved that problem using recursion. C++

1. Find Greatest Common Divisor (GCD) of 2 numbers using recursion.

2. Write a recursive function to reverse a string. Write a recursive function to reverse the words in a string, i.e., boy is walking becomes Walking is boy.

3. Write a function for mutliply(a,b), where a and b are both positive integers, but you can only use the + or operators.