BoundaryTraversaOfATree.txt

class Solution {
public:
    vector <int> printBoundary(Node *root)
    {
        //Your code here
          vector<int> ans;
          
        if(root==NULL)
        return ans;
        
        ans.push_back(root->data);
        
        lefttree(root->left,ans);
        leafnodes(root,ans);
        righttree(root->right,ans);
        //reverse(ans.begin(),ans.end());
        return ans;
        
    }
    void lefttree(Node* root,vector<int> &ans)
    {
        if(!root)
        {
            return;
        }
        if(root->left!=NULL)
        {
            ans.push_back(root->data);
            lefttree(root->left,ans);
        }
        else if(root->right!=NULL)
        {
            ans.push_back(root->data);
            lefttree(root->right,ans);
        }
    }
    void leafnodes(Node* root,vector<int> &ans)
    {
        if(!root)
        return ;
        
         leafnodes(root->left,ans);
        if(root->left==NULL && root->right==NULL)
        ans.push_back(root->data);
         leafnodes(root->right,ans);
       
        
    }
    void righttree(Node* root,vector<int> &ans)
    {
        if(!root)
        return ;
        if(root->right!=NULL)
        {
            righttree(root->right,ans);
             ans.push_back(root->data);
        }
        else
        if(root->left!=NULL)
        {
            righttree(root->left,ans);
            ans.push_back(root->data);
        }
    }
};