039_二叉树的最大深度

知识点：二叉树、DFS

LeetCode第一百零四题：https://leetcode-cn.com/problems/maximum-depth-of-binary-tree/submissions/

迭代的做法是：定义个数组(队列)，元素类型为map，TreeNode to Int(depth)即可

语言：GoLang

var maxDep int
func maxDepth(root *TreeNode) int {
    maxDep = 0
    dfs(root, 1)
    return maxDep
}

func dfs(root *TreeNode, depth int) {
    if root == nil {
        return
    }

    if depth > maxDep {
        maxDep = depth
    }

    dfs(root.Left, depth + 1)
    dfs(root.Right, depth + 1)
}