Solution

• 递归遍历每个节点

/*
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 || !pRoot2) return false;
        return travel(pRoot1, pRoot2) || HasSubtree(pRoot1->left, pRoot2) || HasSubtree(pRoot1->right, pRoot2);
    }
    
    bool travel(TreeNode* root1, TreeNode* root2) {
        if (root2 == nullptr) return true;
        if (root1 == nullptr) return false;

        return root1->val == root2->val && travel(root1->left, root2->left)
                && travel(root1->right, root2->right);
    }
};