c_cpp 特里

Posted 2021-05-14

#pragma once

#include <string>
#include <map>
#include <queue>

typedef struct TrieNode {
    bool completed;
    std::map<char, TrieNode *> children;
    TrieNode() : completed(false){};
} TrieNode;

class Trie{
    public:
      Trie();
      ~Trie();

      void insert(std::string word);
      bool search(std::string word);

    private:
      TrieNode *root;
};

#include <iostream>
#include <cstdlib>

#include "trie.h"

using namespace std;

Trie::Trie() {
    root = new TrieNode();
}
Trie::~Trie() {
    queue<TrieNode *> data;
    data.push(root);

    //BFS
    while(!data.empty()){
        TrieNode *curr = data.front();
        data.pop();

        for (auto iter = curr->children.begin(); iter != curr->children.end(); ++iter){
            data.push(iter->second);
        }
        delete curr;
    }
}

void Trie::insert(string word) {
    TrieNode *curr = root;
    for (int i = 0; i < word.size(); ++i) {
        if(curr->children.find(word[i]) == curr->children.end())
            curr->children[word[i]] = new TrieNode();
        curr = curr->children[word[i]];
    }
    curr->completed = true;
}

bool Trie::search(string word) {
    TrieNode *curr = root;
    for (int i = 0; i < word.size(); ++i) {
        if(curr->children.find(word[i]) == curr->children.end())
            return false;
        curr = curr->children[word[i]];
    }

    return curr->completed;
}

#include <iostream>
#include <cstdlib>
#include <memory>

#include "trie.h"

#include "../unit_test.h"

//execution flow: 
//set up -> section1 -> tear down -> set up -> section2 -> tear down

// std::unique_ptr<Trie> t = std::make_unique<Trie>();


TEST_CASE("Testing Trie") {
    //set up
    // Trie *t = new Trie();
    std::unique_ptr<Trie> t = std::make_unique<Trie>();

    //different sections
    SECTION("Search an existent word.") {
        std::string word = "abandon";
        t->insert(word);
        REQUIRE(t->search(word) == true);
    }

    SECTION("Search a nonexistent word.") {
        std::string word = "abadon";
        REQUIRE(t->search(word) == false);
    }

    //tear down
    std::cout << "tear down" << std::endl;
    // delete t;
}