本題為劍指offer面試題59

• 熱度指數：31571  時間限制：1秒  空間限制：32768K

package go.jacob.day609;

public class Demo2 {
	boolean isSymmetrical(TreeNode pRoot) {
		if (pRoot == null)
			return true;
		return isSymmetrical(pRoot.left, pRoot.right);
	}
	//比較左右子樹對應節點是否相同
	private boolean isSymmetrical(TreeNode pRoot1, TreeNode pRoot2) {
		if (pRoot1 == null && pRoot2 == null)
			return true;
		if (pRoot1 == null || pRoot2 == null)
			return false;
		if (pRoot1.val != pRoot2.val)
			return false;

		return isSymmetrical(pRoot1.left, pRoot2.right) && isSymmetrical(pRoot1.right, pRoot2.left);
	}

	class TreeNode {
		int val = 0;
		TreeNode left = null;
		TreeNode right = null;

		public TreeNode(int val) {
			this.val = val;

		}

	}
}