Question

#include <iostream>

using namespace std;

class BinarySearchTree{
   public:
       int size;
       int *array;
      

       BinarySearchTree(int size){
           int newSize = extendSize(size);
           array = new int[newSize];
           for(int x = 0; x < size; ++x){
               array[x] = NULL;
           }
          
       }
}

Given the code above implement the following:

5. Write a function that displays all the left sub
roots of that tree.
6. Write a function that counts and displays the
number of leafs in the tree.

7. Write a function that displays only the leafs of
the tree.

Answer 1

#include <iostream>

using namespace std;

class BinarySearchTree{
   public:
       int size;
       int *array;
      

       BinarySearchTree(int size){
           int newSize = extendSize(size);
           array = new int[newSize];
           for(int x = 0; x < size; ++x){
               array[x] = NULL;
           }
                   this->size = newSize;
       }
           
           void printLeftSubroots() {
                        int start = 0;
                        
                        while(start < size) {
                                cout << array[start];
                                start = 2*start + 1;
                        }          
           }
           
           
           void countLeafs() {
                        int count = 0;
                        for(int i=size-1; i>=0; i++) {
                                if(array[i] != NULL) {
                                        int l = 2*i + 1;
                                        int r = 2*i + 2;
                                        
                                        // if no left and right child present, then it is a leaf
                                        if(l >= size && r>= size) {
                                                count++;
                                        }
                                }                       
                        }
                        cout << "num Leafs: " << count << endl;
           }
           
           void printLeafs() {
                        int count = 0;
                        for(int i=size-1; i>=0; i++) {
                                if(array[i] != NULL) {
                                        int l = 2*i + 1;
                                        int r = 2*i + 2;
                                        
                                        if(l >= size && r>= size) {
                                                cout << array[i] << endl;
                                        }
                                }                       
                        }
           }
}