Boundary traversal.cpp

class Solution {
public:
    void printLeaves(struct Node* root,vector<int>&ans)
{
    if (root == NULL)
        return;

    printLeaves(root->left,ans);

    if (!(root->left) && !(root->right))
         ans.push_back(root->data);

    printLeaves(root->right,ans);
}
void printBoundaryLeft(struct Node* root,vector<int>&ans)
{
    if (root == NULL)
        return;

    if (root->left) {

         ans.push_back(root->data);
        printBoundaryLeft(root->left,ans);
    }
    else if (root->right) {
        ans.push_back(root->data);
        printBoundaryLeft(root->right,ans);
    }
  
}


void printBoundaryRight(struct Node* root,vector<int>&ans)
{
    if (root == NULL)
        return;

    if (root->right) {
        
        printBoundaryRight(root->right,ans);
         ans.push_back(root->data);
    }
    else if (root->left) {
        printBoundaryRight(root->left,ans);
         ans.push_back(root->data);
    }
   
}



vector <int> printBoundary(Node *root)
{
     //Your code here
     vector<int> ans;
     if(root==NULL)
     return ans;
     ans.push_back(root->data);
    printBoundaryLeft(root->left,ans);

    printLeaves(root->left,ans);
    printLeaves(root->right,ans);

 
    printBoundaryRight(root->right,ans);
     return ans;
     
}

};