Using recursion to sum numbers

Question

I have just been studying the concept of recursion and I thought that I would try a simple example. In the following code, I am attempting to take the numbers: 1, 2, 3, 4, 5, an

Answer 1

int summation(int num){

    if (num==1)
        return 1;

    return summation(num-1)+num;
}