Lettcode_100_Same Tree

本文是在学习中的总结，欢迎转载但请注明出处：http://blog.csdn.net/pistolove/article/details/42061529

Given two binary trees, write a function to check if they are equal or not.

Two binary trees are considered equal if they are structurally identical and the nodes have the same value.

思路：

（1）题意为判断两棵树是否完全相同。

（2）这道题很简单，运用递归分别判断左右子树是否相等，即能得到结果。这里不再做详细分析。

（3）题虽简单，也有必要记录一下。希望对你有所帮助。

算法代码实现如下所示：

public static boolean isSameTree(TreeNode r1, TreeNode r2) {
	if (r1 == null && r2 == null) {
		return true;
	}else if (r1 == null || r2 == null) {
		return false;
	}else {
		if (r1.val != r2.val) {
			return false;
		}

		boolean left = isSameTree(r1.left, r2.left);
		boolean right = isSameTree(r1.right, r2.right);

		if (left && right) {
			return true;
		} else {
			return false;
		}
	}
}