题解 | #树的子结构#

/*
struct TreeNode {
	int val;
	struct TreeNode *left;
	struct TreeNode *right;
	TreeNode(int x) :
			val(x), left(NULL), right(NULL) {
	}
};*/
class Solution {
public:
    bool HasSubtree(TreeNode* pRoot1, TreeNode* pRoot2) {
		if(pRoot1==nullptr||pRoot2==nullptr) return false;
		return HasSubtreeHelper(pRoot1,pRoot2)||HasSubtree(pRoot1->left,pRoot2)||HasSubtree(pRoot1->right,pRoot2);
    }

	bool HasSubtreeHelper(TreeNode* pRoot1,TreeNode* pRoot2){
		if(pRoot2==nullptr) return true;
		if(pRoot1==nullptr||pRoot1->val!=pRoot2->val) return false;
		return HasSubtreeHelper(pRoot1->left,pRoot2->left)&&HasSubtreeHelper(pRoot1->right,pRoot2->right);
	}

};