Lab2(1)

#include <iostream>
#include <string>
#include <fstream>
#include <Windows.h>
#include <map>
#include <vector>
#include <algorithm>
using namespace std;

string path, virus_mask;
string path1, path2;
ifstream in("replacement.txt");
vector<pair<string, string> > exchange;
vector<int> z_function(const string &s) {
    int n = (int)s.length();
    vector<int> z(n, 0);
    for (int i = 1, l = 0, r = 0; i < n; i++) {
        if(i <= r)
            z[i] = min(z[i - l], r - i + 1);
        while(z[i] + i < n && s[z[i]] == s[i + z[i]])
            ++z[i];
        if(i  + z[i] - 1 > r)
            l = i, r = i + z[i] - 1;
    }
    return z;
}
vector<pair< pair<int, int>, pair<int, int> > > answer; // от куда до куда заменять в какой строке чем

bool comp(pair<string, string> a, pair<string, string> b) {
    if(a.first.length() > b.first.length())
        return true;
    if(a.first.length() == b.first.length() && a.first < b.first)
        return true;
    return false;

}

bool isVirus(const string &s) {
    vector<int> z = z_function(virus_mask + '#' + s);
    int n = z.size();
    for (int i = 0; i < n; i++) {
        if (z[i] == virus_mask.length()) {
            return z[i];
        }
    }
    return z[n - 1] == virus_mask.length();
}

int main() {
    string s;
    while(getline(in, s)) {
        string pattern, replacement;
        bool f = 0;
        for (int i = 0; i < s.length(); i++) {
            if(s[i] == ' ' ) {
                f = 1;
                continue;
            }
            if(f)
                replacement.push_back(s[i]);
            else
                pattern.push_back(s[i]);
        }
        exchange.push_back(make_pair(pattern, replacement));
    }

    sort(exchange.begin(), exchange.end(), comp);

    in.close();
    in.open("text.txt", ifstream::in);
    s = "";
    int k = 0;
    while(getline(in, s)) {
        int len = s.length();
        for (int i = 0; i < len; i++) {
            int sz = exchange.size();
            for (int j = 0; j < sz; j++) {
                virus_mask = exchange[j].first;
                int t1 = virus_mask.length();
                string str = s.substr(i, t1);
                if(isVirus(str)) {
                    answer.push_back(make_pair(make_pair(i, i + t1),make_pair(k, j)));
                    i += (t1 - 1);
                }
            }
        }
        k++;
    }

    in.close();
    in.open("text.txt", ifstream::in);
    ofstream out("result.txt");
    k = 0;
    int i = 0;

    while(getline(in, s)) {
        int len = s.length();
        for (int j = 0; j < len; j++) {
            if(i < answer.size() && answer[i].second.first == k && answer[i].first.first == j) {
                j += exchange[answer[i].second.second].first.length();
                out << exchange[answer[i].second.second].second;
                i++;
                j--;
            }
            else
                out << s[j];
        }
        k++;
        out << endl;
    }
    return 0;
}