Boyer-Moore字符串搜索查找精确和相似的匹配项

Question

我一直试图制作一个搜索程序来搜索.txt文件中的模式，该文件包含100000个单词。我想查找并打印完全相同的匹配项。我从文件读取并将其传递给大小为125000的char数组（我知道这很糟糕），而 BoyerMooreSearch 函数为我提供了索引（输出的索引[125000 char数组]模式匹配），但我无法执行任何操作。

我在想这可能创建一个链表并仅传递 BoyerMooreSearch 函数创建的模式吗？但是，即使我设法通过.txt中找到的完全匹配项，我如何在Boyer-Moore搜索中找到相似的匹配项？任何帮助将不胜感激。

在研究代码之前，前三个功能只是对Boyer-Moore的预处理，主要搜索功能是 BoyerMooreSearch ，以防止浪费时间。

#include <iostream>
#include <fstream>
#include <string>
#include <chrono>  //For time

using namespace std;

#define NO_OF_CHARS 256

void badCharHeuristic(char *str, int size, int badchar[NO_OF_CHARS])
{
    int i;

    for (i = 0; i < NO_OF_CHARS; i++)
        badchar[i] = -1;

    for (i = 0; i < size; i++)
        badchar[str[i]] = i;
}

void bmPreprocess1(char *pat, int *f, int *s)
{
    int m = strlen(pat);

    for (int k=0; k < m+1; k++) 
        s[k] = 0;

    int i = m, j = m + 1;
    f[i] = j;

    while (i > 0)
    {
        while (j <= m && pat[i-1] != pat[j-1]) {
            if (s[j] == 0) 
            { 
                s[j] = j - i ;
                j = f[j];
            }
            if (s[j] != 0)
                break;
        }
        i--; j--;
        f[i] = j;
    }
}

void bmPreprocess2(char *pat, int *f, int *s)
{
    int m = strlen(pat);

   for (int k=0; k < m+1; k++) 
        s[k] = 0;

    int i, j;
    j = f[0];

    for (i=0; i <= m; i++) {
        if (s[i] == 0) 
            s[i] = j;
        if (i == j) 
            j = f[j];
    }
}

void BoyerMooreSearch(char *txt, char *pat)
{
    int m = strlen(pat);
    int n = strlen(txt);

    int *f = new int[m+1];
    int *s = new int[m+1];

    int badchar[NO_OF_CHARS];

    badCharHeuristic(pat, m, badchar);
    bmPreprocess1(pat, f, s);
    bmPreprocess2(pat, f, s);

    int k = 0;  // holds the value of how many shifts we are going to make
    while (k <= (n - m))
    {
        int j = m - 1;

        while (j >= 0 && pat[j] == txt[k + j])
            j--;

        if (j < 0)
        {
            k += (k + m < n) ? m - badchar[txt[k + m]] : 1;   
            cout << "pattern occurs at shift = " << k << "\n";
        }
        else {
            k += max(1, j - badchar[txt[k + j]]);
        }
    }
}

int main()
{
    char *p = new char[10];
    cin >> p;
    ifstream readfile;
    readfile.open("englishlinebyline.txt");
    char *output = new char[125000];
    while (!readfile.eof())
    {
        for (int i=0; i <= 125000; i++)
            readfile >> output[i];
    }
    clock_t timepassed = clock();
    BoyerMooreSearch(output, p);
    timepassed = clock() - timepassed;
    double timepassed2 = ((double)timepassed / CLOCKS_PER_SEC);
    cout << "\nfound in " << timepassed2 << " nanoseconds.\n";
    output = NULL;
    delete output;

    system("pause");
    return 0;
}