題目描述
請(qǐng)實(shí)現(xiàn)一個(gè)函數(shù)叮贩，用來(lái)判斷一顆二叉樹是不是對(duì)稱的颅湘。注意话侧，如果一個(gè)二叉樹同此二叉樹的鏡像是同樣的，定義其為對(duì)稱的闯参。
public class Solution {
boolean isSymmetrical(TreeNode pRoot) {
if(pRoot == null)
return true;
return compare(pRoot.left, pRoot.right);
}
boolean compare(TreeNode left, TreeNode right) {
if(left == null && right == null)
return true;
if(left == null || right == null)
return false;
if(left.val == right.val) {
return compare(left.left, right.right) && compare(left.right, right.left);
}else
return false;
}
}
