LeetCode || Minimum Depth of Binary Tree

原创于 2015-07-29 17:37:33 发布 · 306 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#Tree #Depth-First Search #Breadth-First Search #LeetCode

LeetCode 专栏收录该内容

107 篇文章

订阅专栏

本文介绍了一种求解二叉树最小深度的算法实现，通过深度优先搜索(DFS)遍历二叉树来找到从根节点到最近叶子节点的最短路径。此算法适用于计算机科学中的数据结构与算法课程，帮助理解二叉树的基本操作。

Minimum Depth of Binary Tree

题目链接耗时：12ms。

Given a binary tree, find its minimum depth.

The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.

<span style="font-size:14px;">/**
 * 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 minD = 1<<30;
    int currDepth = 0;
    void dfs(TreeNode* root)
    {
        if(root->left == NULL && root->right == NULL)//leaf node
        {
            if(currDepth < minD)
                minD = currDepth;
            return;
        }
        
        //dfs左子树
        if(root->left!=NULL)
        {
            currDepth++;
            dfs(root->left);
            currDepth--;
        }
        //dfs右子树
        if(root->right!=NULL)
        {
            currDepth++;
            dfs(root->right);
            currDepth--;
        }
        
    }
    int minDepth(TreeNode* root) {
        if(root == NULL)
            return 0;
        
        currDepth = 1;
        dfs(root);
        
        return minD;
    }
};</span>