输入两棵二叉树A,B,判断B是不是A的子结构。(ps:我们约定空树不是任意一个树的子结构)
/*
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 isSubtree(pRoot1, pRoot2)|| HasSubtree(pRoot1->left,pRoot2) || HasSubtree(pRoot1->right,pRoot2);
}
bool isSubtree(TreeNode* pRoot1 , TreeNode* pRoot2){
if(pRoot2 == nullptr)
return true;
if(pRoot1 == nullptr)
return false;
return pRoot1->val == pRoot2->val && isSubtree(pRoot1->left,pRoot2->left) && isSubtree(pRoot1->right,pRoot2->right);
}
};