minimum_depth_of_binary_tree.go

package problem111

import "github.com/awesee/leetcode/internal/kit"

// TreeNode - Definition for a binary tree node.
type TreeNode = kit.TreeNode

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func minDepth(root *TreeNode) int {
	if root == nil {
		return 0
	}
	l := minDepth(root.Left)
	r := minDepth(root.Right)
	if l == 0 || r == 0 {
		return l + r + 1
	}
	if l < r {
		return l + 1
	}
	return r + 1
}