Kth Smallest Element in a BST @LeetCode

PROBLEM :

Given a binary search tree, write a function kthSmallest to find the kth smallest element in it.

Note:
You may assume k is always valid, 1 ? k ? BST's total elements.

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SIMPLE c++ IMPLEMENTATION :
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/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */

class Solution {
public:
    int kthSmallest(TreeNode* root, int k) {
        int min ;
        KthSallestEle(root,&k,&min) ;
        return min ;
    }
   
    void KthSallestEle(TreeNode *root,int *k,int *min){
        if(root->left)
            KthSallestEle(root->left,&(*k),&(*min)) ;
        (*k)-- ;
        if((*k)==0){
            (*min)=root->val ;
            return ;
        }
        if(root->right)
            KthSallestEle(root->right,&(*k),&(*min)) ;
    }
};

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