Thread: Binary trees

Hello, I just got this assignment on binary trees, its just tracing through and seeing what numbers i end up with. I dont know how to read this and get the acctual answers. I can put it into visual studio and get it but would it be possible for any of you to explain to me of how this program specificly works?? thanks

Code:

   1. Consider the program:

      #include <iostream>
      using namespace std;

      void p(int x)
      {
        if (x < 0) return;
        p(x-1);
        cout << x << endl;
        p(x-2);
      }

      main()
      {
        int y;
        while (cin >> y, y >= 0) {
          p(y);
          cout << "*************" << endl;
        }
      }

      Trace the program by hand to get the output of p(0), p(1), p(2), p(3) and p(4).

   2. Conisder the program:

      #include <iostream>
      using namespace std;

      void p(char A[], int m, int n)
      {
      	if (m == n) {
      		for (int i = 0; i < n; i++) cout << A[i];
      		cout << endl;
      		return;
      	}
      	for (char c = 'A'; c <= 'C'; c++) {
      		A[m] = c;
      		p(A,m+1,n);
      	}
      }

      main()
      {
      	char B[10];
      	int k;
      	cin >> k;
      	p(B,0,k);
      }

      Trace this program by hand and determine for nonnegative integer k, what is the output of p(B,0,k).

I don't have the knowledge to explain, but here are some really great explanations:
http://www.eternallyconfuzzled.com/t..._tut_bst1.aspx