513. Find Bottom Left Tree Value（DFS）

题目：查找二叉树的最底部的最左的节点的值

/**
 * 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 bottomval = 0;
    int level = 0;
    int findBottomLeftValue(TreeNode* root) {     
        findValue(root,1,level,bottomval);
        return bottomval;      
    }

    void findValue(TreeNode* root,int depth,int &level,int &bottomval) 
    {
        if(!root)
          return;
        if(depth>level)
        {
            bottomval = root->val;
            level = depth;
        }
        findValue(root->left,depth+1,level,bottomval);
        findValue(root->right,depth+1,level,bottomval);
           
    }    
        
    
};