[LeetCode] 572. Subtree of Another Tree - Java

• 문제 링크

Subtree of Another Tree - LeetCode

 

• 풀이 코드

public class Solution {

    public boolean isSubtree(TreeNode root, TreeNode subRoot) {
        if (root == null) return false;
        if (isSameTree(root, subRoot)) return true;

        return isSubtree(root.left, subRoot) || isSubtree(root.right, subRoot);
    }

    private boolean isSameTree(TreeNode a, TreeNode b) {
        if (a == null && b == null) return true;
        if (a == null || b == null || a.val != b.val) return false;

        return isSameTree(a.left, b.left) && isSameTree(a.right, b.right);
    }

}