Binary Tree Paths
描述
Given a binary tree, return all root-to-leaf paths.
For example, given the following binary tree:
1
/ \
2 3
\
5
All root-to-leaf paths are:
["1->2->5", "1->3"]
Credits:Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.
题解
package algorithms
import (
"github.com/ljun20160606/leetcode/algorithms"
"strconv"
"strings"
)
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
type TreeNode = algorithms.TreeNode
func binaryTreePaths(root *TreeNode) []string {
var result []string
helper(root, &result, []string{})
return result
}
func helper(root *TreeNode, result *[]string, temp []string) {
if root == nil {
return
}
temp = append(temp, strconv.Itoa(root.Val))
if root.Left == nil && root.Right == nil {
*result = append(*result, strings.Join(temp, "->"))
return
}
helper(root.Left, result, temp)
helper(root.Right, result, temp)
}