在程序设计实验用了一下类

#include "stdafx.h"

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <algorithm>
using namespace std;

#define EQUAL 0
#define WORDLEN 200
#define CHAR_COUNT 26

struct word {
    char name[WORDLEN];
    int fre[CHAR_COUNT];
};

class dict {
    static const int DICTVOL = 100;
    word list[DICTVOL];
    int wordcount;
public:
    dict();
    void addword(const char str[]);
    void search(const char req[]);
    void dictsort();
    friend void calfre(word & tar);
    friend bool frecmp(word & w1, word & w2);
};


void calfre(word & tar) //log the frequency of each char
{
    for (int i = 0; i < CHAR_COUNT; i += 1)
        tar.fre[i] = 0;
    for (int i = 0; tar.name[i] != ''; i += 1) 
        tar.fre[tar.name[i] - 'a'] += 1;
}
bool frecmp(word &w1, word &w2) 
{
    for (int i = 0; i < CHAR_COUNT; i += 1)
    {
        if (w1.fre[i] != w2.fre[i])
            return false;
    }
    return true;
}
bool dictcmp(word & a, word & b)
{
    if (strcmp(a.name, b.name) < 0) return true;
    else return false;
}
dict::dict()
{
    memset(list,0,sizeof(list));
    wordcount = 0;
}
void dict::addword(const char str[])
{
    strcpy_s(list[wordcount].name, str);
    calfre(list[wordcount]);
    wordcount += 1;
}
void dict::search(const char req[])
{
    bool found = false;
    word temp;
    strcpy_s(temp.name, req);
    calfre(temp);

    for (int i = 0; i < wordcount; i += 1)
    {
        if (frecmp(list[i], temp) == true)
        {
            cout << list[i].name << endl;
            found = true;
        }
    }
    if (found == false)
        cout << "NOT A VALID WORD" << endl;
    cout << "******" << endl;
}
void dict::dictsort()
{
    word temp[DICTVOL];
    for (int i = 0; i < wordcount; i += 1)
        temp[i] = list[i];
    sort(temp, temp + wordcount, dictcmp);
    for (int i = 0; i < wordcount; i += 1)
        list[i] = temp[i];
}

int main()
{
    dict d;
    char temp[WORDLEN];
    cin >> temp;
    while (strcmp(temp, "XXXXXX") != EQUAL)
    {
        d.addword(temp);
        cin >> temp;
    }
    d.dictsort();
    cin >> temp;
    while (strcmp(temp, "XXXXXX") != EQUAL)
    {
        d.search(temp);
        cin >> temp;
    }
    return 0;
}