572. Subtree of Another Tree.go

package leetcode

import (
	"github.com/halfrost/LeetCode-Go/structures"
)

// TreeNode define
type TreeNode = structures.TreeNode

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */

func isSubtree(s *TreeNode, t *TreeNode) bool {
	if isSameTree(s, t) {
		return true
	}
	if s == nil {
		return false
	}
	if isSubtree(s.Left, t) || isSubtree(s.Right, t) {
		return true
	}
	return false
}

// this is 100 solution
func isSameTree(p *TreeNode, q *TreeNode) bool {
	if p == nil && q == nil {
		return true
	} else if p != nil && q != nil {
		if p.Val != q.Val {
			return false
		}
		return isSameTree(p.Left, q.Left) && isSameTree(p.Right, q.Right)
	} else {
		return false
	}
}