Count Leaf Nodes In a Generic Tree (Recursively) - c++

Question

I am trying to make a C++ program to count the number of Leaf Nodes in a generic tree using a Recurisve approach.
here is my code:
int countLeafNodes(TreeNode<int> *root)
{
if (root = NULL)
{
return 0;
}
int total = 0;
if (root->children.size() == 0)
{
return 1;
}
for (int i = 0; i < root->children.size(); i++)
{
total += countLeafNodes(root->children[i]);
}
return total;
}
int main()
{
TreeNode<int> *root = takeInputLevelWise();
cout << "Total Leaf Nodes = " << countLeafNodes(root) << endl;
return 0;
}
But I don't get any output on my editor (vs code) so I tested it on an online judge and it was giving SIGSEGV error. I know we get that error for an Invalid memory reference but I don't understand where in my code I am doing that mistake. Please someone tell me what's wrong with the code and why it is not working.
here is the complete code:
#include <bits/stdc++.h>
using namespace std;
template <typename T>
class TreeNode
{
public:
T data;
vector<TreeNode<T> *> children;
TreeNode(T data)
{
this->data = data;
}
~TreeNode()
{
for (int i = 0; i < children.size(); i++)
{
delete children[i];
}
}
};
TreeNode<int> *takeInputLevelWise()
{
int rootData;
cout << "Enter Root Data" << endl;
cin >> rootData;
TreeNode<int> *root = new TreeNode<int>(rootData);
queue<TreeNode<int> *> pendingNode;
pendingNode.push(root);
while (!pendingNode.empty())
{
TreeNode<int> *front = pendingNode.front();
pendingNode.pop();
int numChild;
cout << "Enter number of children of " << front->data << endl;
cin >> numChild;
for (int i = 0; i < numChild; i++)
{
int childData;
cout << "Enter " << i << "th child of " << front->data << endl;
cin >> childData;
TreeNode<int> *child = new TreeNode<int>(childData);
front->children.push_back(child);
pendingNode.push(child);
}
}
return root;
}
int countLeafNodes(TreeNode<int> *root)
{
if (root = NULL)
{
return 0;
}
int total = 0;
if (root->children.size() == 0)
{
return 1;
}
for (int i = 0; i < root->children.size(); i++)
{
total += countLeafNodes(root->children[i]);
}
return total;
}
int main()
{
TreeNode<int> *root = takeInputLevelWise();
cout << "Total Leaf Nodes = " << countLeafNodes(root) << endl;
return 0;
}
I am pretty sure there is no problem with the TreeNode class or takeInputLevelWise() function as I have used the same code in many other questions to generate the tree. The problem must be in the countLeafNodes() function.

Answer 1

There is a problem in your countLeafNodes function.
if (root = NULL)
{
return 0;
}
Hope you find the error.