Problems creating Binary Tree

Hi all,

I'm doing an exercise from a book to design and draw a binary tree, with the constructor simply taking the number of levels as a constructor.

I have it creating the correct number of nodes for the required level, however I am having trouble using the module operator within the constructor.

This code works:

Code:

---

Binary_tree::Binary_tree(int l)
:levels(l)
{
                if(levels>0)
                        add(Point(100,100));
                        nodes=pow(2.0, levels)-1;
                       
                        for(int i = 1; i< nodes; ++i) {
                               
                                add(Point(point(i-1).x+50, point(i-1).y+50));       
                        }
}

---

The problem is I obviously want the nodes to go left/right. So I used the modulo remainder to determine if the node is odd/even as such:

Code:

---

Binary_tree::Binary_tree(int l)
:levels(l)
{
                if(levels>0)
                        add(Point(100,100));
                        nodes=pow(2.0, levels)-1;
                       
                        for(int i = 1; i< nodes; ++i) {
                                if(i%2 == 0)
                               
                                add(Point(point(i-1).x+50, point(i-1).y+50));       
                        }
}

---

However, I get a windows error box appearing saying vector subscript out of range? Any ideas?

Thanks.

Please ignore. Have figured it out.

By the way, you could avoid #include <cmath> and the use of std::pow by changing:

Code:

---

nodes=pow(2.0, levels)-1;

---

to:

Code:

---

nodes = (1U << levels) - 1;

---

Quote:

---

Originally Posted by laserlight

By the way, you could avoid #include <cmath> and the use of std::pow by changing:

Code:

---

nodes=pow(2.0, levels)-1;

---

to:

Code:

---

nodes = (1U << levels) - 1;

---

---

What does the 1U mean?

Thanks.

1 Unsigned.