HDU-1247 Hat’s Words(单词查找树)

Problem Description

A hat’s word is a word in the dictionary that is the concatenation of exactly two other words in the dictionary. You are to find all the hat’s words in a dictionary.

Input

Standard input consists of a number of lowercase words, one per line, in alphabetical order. There will be no more than 50,000 words. Only one case.

Output

Your output should contain all the hat’s words, one per line, in alphabetical order.

Sample Input

a
ahat
hat
hatword
hziee
word

Sample Output

ahat
hatword

---

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

using namespace std;

class TrieNode{
public:
    int wordNum;
    bool isWord; //到当前字符为止是否是一个完整的单词
    TrieNode *child[26];

    TrieNode() : wordNum(0), isWord(false) {
        for (auto & a : child) a = nullptr;
    }
};

class Trie {
public:
    /** Initialize your data structure here. */
    Trie() {
        root  = new TrieNode();
    }

    ~Trie(){
        clear();
    }

    /** Inserts a word into the trie. */
    void insert(string word) {
        TrieNode *p = root;
        ++(p -> wordNum);

        for (auto &a : word){
            int id = a - 'a';
            if (!p -> child[id]) p -> child[id] = new TrieNode();
            p = p -> child[id];
            ++(p -> wordNum);
        }

        p -> isWord = true;
    }

    /** Returns if the word is in the trie. */
    int search(string word) {
        TrieNode *p = root;

        for (auto a : word){
            int id = a - 'a';
            if (!p -> child[id]) return 0;
            p = p -> child[id];
        }

        return p -> wordNum;
    }

    void clear()
    {
        remove(root);

        for (int i = 0; i < 26; ++i)
            root -> child[i] = nullptr;
    }

private:
    TrieNode *root;

    void remove(TrieNode * &p)
    {
        for (int i = 0; i < 26; ++i){
            if (!p -> child[i]) continue;
            remove(p -> child[i]);
            delete p -> child[i];
            p -> child[i] = nullptr;
            if ( (--(p -> wordNum)) == 0 ) break;
        }
    }
};

int main()
{
    vector<string> store;
    Trie trie;
    string inputStr;

    while(cin >> inputStr){
        trie.insert(inputStr);
        store.push_back(inputStr);
    }

    for (size_t i = 0; i < store.size(); ++i){
        for (size_t j = 1; j < store[i].size(); ++j){
            string tmp1 = store[i].substr(0, j);
            string tmp2 = store[i].substr(j, store[i].size());
            if (trie.search(tmp1) && trie.search(tmp2)){
                cout << store[i] << endl;
                break;
            } 
        }
    }

    return 0;
}

查找单词的思路是顺序遍历数组中的每个单词，将每个单词拆分成两个单词并进行查找，只要找到一个就跳出内层循环并输出，但是此代码一直得到Wrong Answer