算法分析与设计丨第四周丨LeetCode（7）——Find Bottom Left Tree Value（Medium）

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题目链接：https://leetcode.com/problems/find-bottom-left-tree-value/description/

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