传送到leetcode: leetcode-104

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
29
30
31
32
33
/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
// dfs实现
func maxDepth(root *TreeNode) int {
    max := 0
    startDeep := 0

    var dfs func(node *TreeNode, startDeep int)
    dfs = func(node *TreeNode, startDeep int) {
        if node == nil {
            return
        }
        startDeep = startDeep + 1

        if node.Left == nil && node.Right == nil {
            if startDeep > max {
                max = startDeep
            }
        }

        dfs(node.Left, startDeep)
        dfs(node.Right, startDeep)
    }

    dfs(root, startDeep)
    return max
}