check existence of a path having given sum

#include<iostream>
#include<vector>
using namespace std;

class Node{
  public:
      int data;
      Node *left,*right;
      Node(int key){
        data=key;
        left=NULL;
        right=NULL;
        }
  };

int CheckExistence(Node* root,int sum){
  if(root==NULL)
    return 0;
  sum=sum-root->data;
  if(sum>0)
    return CheckExistence(root->left,sum)||CheckExistence(root->right,sum);
  if(sum)
    return 0;
  else
    return 1;
  }

int main(){
  Node *root=NULL;
  Node *newnode=new Node(1);
  root=newnode;
  root->left=new Node(9);
  root->right=new Node(3);
  (root->left)->left=new Node(2);
  (root->right)->right=new Node(4);
  if(CheckExistence(root,9))
  cout<<"yes";
  else
    cout<<"no";
  return 0;
  }