Commit 13615d1

committed

Add solution 110.

1 parent 3d645ea commit 13615d1Copy full SHA for 13615d1

File tree

+30

-0

lines changed

+30

-0

lines changed

Lines changed: 30 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,30 @@`
	`1`	`+/**`
	`2`	`+ * Definition for a binary tree node.`
	`3`	`+ * class TreeNode {`
	`4`	`+ * public $val = null;`
	`5`	`+ * public $left = null;`
	`6`	`+ * public $right = null;`
	`7`	`+ * function __construct($value) { $this->val = $value; }`
	`8`	`+ * }`
	`9`	`+ */`
	`10`	`+class Solution {`
	`11`	`+`
	`12`	`+ /**`
	`13`	`+ * @param TreeNode $root`
	`14`	`+ * @return Boolean`
	`15`	`+ */`
	`16`	`+ function isBalanced($root) {`
	`17`	`+ return $root == null \|\| self::checkDepth($root) != -1;`
	`18`	`+ }`
	`19`	`+`
	`20`	`+ function checkDepth($root) {`
	`21`	`+ $lh = $root->left == null ? 0 : self::checkDepth($root->left);`
	`22`	`+ $rh = $root->right == null ? 0 : self::checkDepth($root->right);`
	`23`	`+ // Left subtree or right subtree is unbalanced`
	`24`	`+ if ($lh == -1 \|\| $rh == -1) return -1;`
	`25`	`+ // This tree is unbalanced`
	`26`	`+ if ($lh - $rh > 1 \|\| $lh - $rh < -1) return -1;`
	`27`	`+ // Return depth of this tree`
	`28`	`+ return max($lh, $rh) + 1;`
	`29`	`+ }`
	`30`	`+}`

Comments

(0)