Cod sursa(job #2370737)

Utilizator Fatu_SamuelFatu Samuel Fatu_Samuel Data 6 martie 2019 13:30:45
Problema Potrivirea sirurilor Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.33 kb
#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("strmatch.in");
ofstream fout("strmatch.out");

string txt, pat;
int prefix[2000001];
int cate = 0;

void KMP(string txt, string pat)
{
    int lenTxt = txt.length();
    int lenPat = pat.length();

    int i = 0, j = 0;

    while(i < lenTxt)
    {
        if(pat[j] == txt[i])
            i++, j++;

        if(j == lenPat)
        {
            cate++;

            if(cate <= 1000)
                fout << i - j << ' ';

            j = prefix[j - 1];
        }
        else if(i < lenTxt && pat[j] != txt[i])
        {
            if(j)
                j = prefix[j - 1];
            else
                i++;
        }
    }
}

void MakePrefix()
{
    int len = 0, i = 1, lenPat = pat.length();

    while(i < lenPat)
    {
        if(pat[i] == pat[len])
            prefix[i++] = ++len;
        else
        {
            if(len)
                len = prefix[len - 1];
            else
                prefix[i++] = 0;
        }
    }
}

int main()
{
    fout << "                                  \n";
    fin >> pat >> txt;
    MakePrefix();
    KMP(txt, pat);
    fout.close();
    fout.open("strmatch.out", ios::in | ios::out);
    fout << cate;

    fin.close();
    fout.close();
    return 0;
}