树的子结构

题目描述

输入两颗二叉树A，B，判断B是不是A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 DFS(TreeNode* pRoot1, TreeNode* pRoot2)
    {
        if ( pRoot1->val != pRoot2->val)
            return 0;
        bool b1,b2;
        if (pRoot1->left != NULL && pRoot2->left != NULL)
        {
            b1 = DFS(pRoot1->left,pRoot2->left);
        }
        else if (pRoot2->left == NULL)
        {
            b1 = 1;
        }
        else
        {
            b1 = 0;
        }

        if (pRoot1->right != NULL && pRoot2->right != NULL)
        {
            b2 = DFS(pRoot1->right,pRoot2->right);
        }
        else if (pRoot2->right == NULL)
        {
            b2 = 1;
        }
        else
        {
            b2 = 0;
        }

        return b1 && b2;
    }
    bool HasSubtree(TreeNode* pRoot1, TreeNode* pRoot2)
    {
        if (pRoot1 == NULL || pRoot2 == NULL)
            return 0;
        std::queue<TreeNode*> qq;
        qq.push(pRoot1);
        bool is = 0;
        while(!qq.empty())
        {
            TreeNode* tem = qq.front();
            qq.pop();
            if(is = DFS(tem,pRoot2))
                return 1;
            if (tem->left != NULL)
                qq.push(tem->left);
            if (tem->right != NULL)
                qq.push(tem->right);
        }
        return 0;
    }
};