LeetCode题解之Find Bottom Left Tree Value

1、题目描述

2、问题分析

使用层序遍历思想

3、代码

int findBottomLeftValue(TreeNode* root) {
        if (root == NULL)
            return 0;
        queue<TreeNode*> q;
        q.push(root);
        
        int val = 0;
       while (!q.empty()) {
            int size = q.size();
            for(int i = 0; i < size; i++) {
                TreeNode *node = q.front();
                if (node->left != NULL)
                    q.push(node->left);
                if (node->right != NULL)
                    q.push(node->right);
                    
                
                if (i == 0)
                   val = node->val;
                q.pop();
            }
        }
        return val;
    }