leetcode-explore-challenge-card-june-leetcoding-challenge-539-week-1-june-1st-june-7th-3347.cpp

class Solution {
public:
    TreeNode* invertTree(TreeNode* root) {
        
        if(root==NULL){
            return NULL;
        }
        
        invertTree(root->left);
        
     invertTree(root->right);
        
        TreeNode * temp=root->left;
        root->left=root->right;
        root->right=temp;
        
        return root;       
    }
};