Question

我正在研究一个应该采用mxn字符数组的程序，基本上是一个单词搜索，并找到这个拼图中的所有单词（向前，向上，向下，向后和对角线）在字典里。我的代码中的所有内容都有效，直到我尝试将字典存储到哈希表中（我需要为分配执行此操作）。到目前为止，这是我的代码以及相关的.h和.cpp文件：

hash_table.h：

#ifndef HASH_TABLE_H
#define HASH_TABLE_H

#include <vector>
#include <iostream>
#include <list>
#include <string.h>

// WANT: support a collection of n items and
//       fast implementation of the following operations
//       FIND(x): returns true iff x is in collection
//       INSERT(x): x is added to collection
//       DELETE(x): x is removed from collection

class hash_table
{
public:

    // CONSTANTS AND TYPES

    static const int DEFAULT_TABLE_SIZE = 20;
    typedef std::string value_type;

    // CONSTRUCTORS

    hash_table(int table_size = DEFAULT_TABLE_SIZE);

    // CONSTANT MEMBERS

    // pre:
    // post: returns yes iff key is in this hash table
    bool find(const value_type & key) const;

    // pre:
    // post: key has been added to this hash table
    //       if it was not this hash table
    //       else do nothing
    void insert(const value_type &key);

    // pre:
    // post: key has been deleted from this hash table
    //       if it was in this table; otherwise do nothing
    void erase(const value_type & key);

private:
    std::vector<std::list<value_type> > table;

    // pre:
    // post: returns a table index corresponding to key
    std::size_t hash(const value_type & key) const;
};

#endif // HASH_TABLE_H

hash_table.cpp：

#include "hash_table.h"

std::size_t hash_table::hash(const value_type & key) const
{
    std::size_t h = 0;
    for (int i = 0; i < key.length(); ++i)
    {
        h = 5*h + key[i];
    }
    return h;
}

hash_table::hash_table(int table_size)
{
    table = std::vector<std::list<value_type> >(table_size, std::list<value_type>());
}

bool hash_table::find(const value_type &key) const
{
    std::list<value_type> l = table[hash(key)];

    std::list<value_type>::const_iterator i;

    for (i = l.begin(); i != l.end(); ++i)
    {
        if (*i == key)
        {
            std::cout << hash(key);
            return true;
        }
    }
    return false;
}

void hash_table::insert(const value_type & key)
{
    if (find(key))
    {
        return;
    }
    table[hash(key)].push_front(key);
}

void hash_table::erase(const value_type & key)
{
    std::list<value_type> & l = table[hash(key)]; // note that l is a reference variable
    std::list<value_type>::iterator i;

    for (i = l.begin(); i != l.end(); ++i)
    {
        if (*i == key)
        {
            l.erase(i);
            return;
        }
    }
}

最后，main.cpp：

#include <iostream>
#include <vector>
#include <fstream>
#include <string.h>
#include <algorithm>
#include "hash_table.h"

using namespace std;

int load(string dict[])
{
    ifstream ds("dictionary.txt");
    if (ds.fail())
    {
        cout << "File I/O error!" << endl;
        exit(2);
    }
    string word;
    int size(0);
    while (ds >> word)
        dict[size++] = word;

    sort(dict, dict+size);
    return size;
}

int main()
{

    int m(0), n(0);
    cout << "Enter dimensions of array: ";
    cin >> m >> n;
    cout << endl;

    ifstream puzzle("puzzle.txt");
    if (puzzle.fail())
    {
        cout << "Error!" << endl;
        exit(2);
    }
    char letters[m][n];

    while (puzzle.good())
    {
        for (int i = 0; i < m; ++i)
        {
            for (int j = 0; j <= i; ++j)
            {
                letters[i][j] = puzzle.get();
            }
        }
    }

    cout << "YOUR WORD SEARCH PUZZLE: " << endl << endl;
    for (int i = 0; i < m; ++i)
    {
        for (int j = 0; j <= i; ++j)
        {
            cout << letters[i][j];
        }
    }

    string dict[100000];
    int size = load(dict);
    hash_table dic(size);

    for (int c = 0; c < size; ++c)
    {
        dic.insert(dict[c]);
    }

    return 0;
}

一旦代码到达最终的for循环就会出现问题，然后程序崩溃。＆＃34; main.exe已停止工作，windows正在寻找解决方案....＆＃34;

将字典文本文件加载到哈希表中的问题

0 个答案: