Understanding c Code Tower of Hanoi using Recursion

Question

I'm studying about recursion in C++, but the following C++ code used to solve the Tower of Hanoi issue has me baffled.

void Hanoi(int m, string start, string middle, string end){
    cout << "m is equal to: " << m << endl;
    if(m == 1){
        cout << "Move Disc " << " from " << start << "  to " << end << endl;
    }
    else{
        Hanoi(m-1,start,end,middle);
        cout << "Move disc " << m << " from " << start << " to " << end << endl;
        Hanoi(m-1,middle,start,end);
    }
}
int main(){
    int discs = 3;
    Hanoi(discs, "start","middle","end");

}

the output of the code is as follows:

m is equal to: 3
m is equal to: 2
m is equal to: 1
Move Disc  from start  to end
Move disc 2 from start to middle
m is equal to: 1
Move Disc  from end  to middle
Move disc 3 from start to end
m is equal to: 2
m is equal to: 1
Move Disc  from middle  to start
Move disc 2 from middle to end
m is equal to: 1
Move Disc  from start  to end

My general issue is that I don't understand how the recursion works. 

Why does m increment to 1 before executing the "if" statement? 

How does m return to 2?

Answer 1

Let's begin with the first section of the output:

m is equal to: 3

m is equal to: 2

m is equal to: 1

The Hanoi function is initially referred to as: Hanoi (3).

Because m!= 1 in this scenario, we shall call Hanoi(m-1) once again.

This will result in the output seen above.

We are now three layers inside this function.

Since m == 1, we will now get the following result:

Move the Disc from beginning to finish.

We now leave the deepest function and return to level 2 of our function call stack.

We now output:

Move disc 2 from beginning to middle.