题解 | #树的子结构#

/** public class TreeNode { int val = 0; TreeNode left = null; TreeNode right = null;

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

}

} */ //史上最烂代码 public class Solution { public boolean HasSubtree(TreeNode root1,TreeNode root2) { if(root2 == null || root1 == null) return false; boolean flag = false;

	if(root1.val == root2.val) {
		if(isEqual(root1, root2)) flag = true;
	}
	if(!flag && HasSubtree(root1.left, root2)) {
		flag = true;
	}
	if(!flag && HasSubtree(root1.right, root2)) flag = true;
	
    return flag;
}

public boolean isEqual(TreeNode root1,TreeNode root2) {
    if(root1==null && root2==null) return true;
	if(root1==null && root2!=null) return false;
	if(root1!=null && root2==null) return true;
	
	boolean flag = false;
	
	if(root1.val == root2.val) {
		if(isEqual(root1.left, root2.left) && isEqual(root1.right, root2.right)) flag = true;
	}
	
	return flag;
}

}