广度优先遍历是一种用于遍历或搜索图（Graph）和树（Tree）数据结构的算法。它的核心思想是从某个起始节...
然后,根据解析重新背着写完这道题,并总结它的规律,及时应用于下一道题的训练。 今天的笔记包含基于树的宽度优先搜索(Tree Breadth-First Search)类型下的5个题目,它们在leetcode上的编号和题名分别是: 102 - Binary Tree Level Order Traversal 107 - Binary Tree Level Order Traversal II 103 - Binary Tree Z...
@return: an integer """defnumIslands(self,grid):# write your code hereifnotgridornotgrid[0]:return0visited=set()result=0foriinrange(len(grid)):forjinrange(len(grid[0])):ifgrid[i][j]and(i,j)notinvisited:self.bfs(grid,i,j,visited)result+=1returnresultdefbfs(self,grid,x,y,visit...
leetcode-14-basic-breadthFirstSearch BFS: breadth first search 107. Binary Tree Level Order Traversal II 解题思路: 本来我是用map<int,int>存所有节点的值和深度(root是0),然后遍历map,result[depth].push_back(val)。但是因为map是无序的,所以 插入的时候,result[i]里元素的顺序会有问题,比如 后面改...
Output: 11 Explanation: Employee 1 has importance value 5, and he has two direct subordinates: employee 2 and employee 3. They both have importance value 3. So the total importance value of employee 1 is 5 + 3 + 3 = 11. Note: ...
[Tree Breadth First Search] 二叉树的锯齿形层次遍历 leetcode 103、Binary Tree Zigzag Level Order Traversal,难度medium 0. 题干 给定一个二叉树,返回其节点值的锯齿形层次遍历。(即先从左往右,再从右往左进行下一层遍历,以此类推,层与层之间交替进行)。 例如: 给定二叉树 [3,9,20,null,null,15,7]...