《leetcode-php》二叉树路径和（两道题放一起）

1.给定一个二叉树和一个值sum，请找出是否存在所有的根节点到叶子节点的节点值之和等于sum的路径。

2.给定一个二叉树和一个值sum，请找出所有的根节点到叶子节点的节点值之和等于sum的路径。

<?php
class Node{
    public $left  = null;
    public $right = null;
    public $val;
    public function __construct($val) {
        $this->val = $val;
    }
}
//是否有
function hasPathSum($root, $sum) {
    if ($root == null) {
        return false;
    }
    if ($root->left == null && $root->right == null) {
        if ($sum = $root->val) {
            return true;
        } else {
            return false;
        }
    }
    $bolLeft  = hasPathSum($root->left, $sum - $root->val);
    $bolRight = hasPathSum($root->right, $sum - $root->val);
    return $bolLeft || $bolRight;
}
//所有路径
function pathSum($root, $sum, &$arrOutput = array()) {
    if ($root == null) {
        return;
    }
    array_push($arrOutput, $root->val);
    if ($root->left == null && $root->right == null && $sum == $root->val) {
        print json_encode($arrOutput)."\n";
    }
    pathSum($root->left, $sum - $root->val, $arrOutput);
    pathSum($root->right, $sum - $root->val, $arrOutput);
    array_pop($arrOutput);
}
$node1  = new Node(5);
$node2  = new Node(4);
$node3  = new Node(8);
$node4  = new Node(11);
$node5  = new Node(13);
$node6  = new Node(4);
$node7  = new Node(7);
$node8  = new Node(2);
$node9  = new Node(5);
$node10 = new Node(1);
$node1->left = $node2;
$node1->right = $node3;
$node2->left = $node4;
$node2->right = $node5;
$node3->left = $node6;
$node4->left = $node7;
$node4->right = $node8;
$node6->left = $node9;
$node6->right = $node10;
$ret = hasPathSum($node1, 22);
print_r($ret);
pathSum($node1, 22);