429. N 叉树的层序遍历

N 叉树的层序遍历

解法一: 深度优先遍历

go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
/**
* Definition for a Node.
* type Node struct {
* Val int
* Children []*Node
* }
*/

func levelOrder(root *Node) [][]int {
ans := [][]int{}
var dfs func(node *Node, depth int)
dfs = func(node *Node, depth int) {
if node == nil {
return
}
if len(ans) <= depth {
ans = append(ans, []int{})
}
ans[depth] = append(ans[depth], node.Val)
depth++
for _, child := range node.Children {
dfs(child, depth)
}
}
dfs(root, 0)
return ans
}

解法二: 广度优先遍历

go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
/**
* Definition for a Node.
* type Node struct {
* Val int
* Children []*Node
* }
*/

func levelOrder(root *Node) [][]int {
ans := [][]int{}
if root == nil {
return ans
}
queue := []*Node{root}
for len(queue) > 0 {
size := len(queue)
nodes := make([]int, size)
for i := 0; i < size; i++ {
nodes[i] = queue[i].Val
for _, child := range queue[i].Children {
queue = append(queue, child)
}
}
queue = queue[size:]
ans = append(ans, nodes)
}
return ans
}
作者

wuhunyu

发布于

2024-02-17

更新于

2025-01-15

许可协议