#include <iostream>
#include <fstream>
#include <Windows.h>
#include <iomanip>

using namespace std;

int main()
{
    SetConsoleCP(1251);
    SetConsoleOutputCP(1251);
    setlocale(LC_ALL, "rus");
    ifstream fin;
    ifstream finS;
    ofstream fout;
    char fileIn[] = "In.txt";
    char fileOut[] = "Out.txt";
    char fileKeys[] = "Keys.txt";
    char fileDecoded[] = "Decoded.txt";
    unsigned char arrin[5000];
    int sum = 0;
    unsigned int keys[5000] = {};
    int ind = 0;
    int size = 0;
    fin.open(fileKeys, ios::binary);
    if (fin.is_open())
    {
        /*cout << "File is opened!\n\n";*/
        while (!fin.eof())
        {
            fin >> arrin;
            for (int i = 0; arrin[i] != '\0'; i++)
            {
                sum += arrin[i];
            }
            keys[ind] = sum % 256;
            sum = 0;
            ind++;
        }
        cout << endl;
    }
    else
    {
        cout << "Reading file error!\n\n";
        system("pause");
        return 0;
    }
    fin.close();

    unsigned char ciphered = 'g';
    fin.open(fileIn, ios::binary);
    fout.open(fileOut, ios::binary);
    if (fout.is_open())
    {
        /*cout << "\"Out\" is opened!\n";*/
    }
    else
    {
        cout << "File opening error!\n\n";
        system("pause");
        return 0;
    }
    if (fin.is_open())
    {
        /*cout << "\"In\" is opened!\n\n";*/
    }
    else
    {
        cout << "File opening error!\n\n";
        system("pause");
        return 0;
    }
    int i = 0;
    while (true)
    {
        fin >> noskipws >> ciphered;
        if (fin.eof())
            break;
        ciphered = (unsigned char)(ciphered ^ keys[i % (ind + 1)]);
        fout << ciphered;
        size++;
        i++;
    }
    i = 0;
    fout.close();
    fin.close();
    /*  fin.open(fileOut);
        fout.open(fileDecoded);
        while (true)
        {
            fin >> noskipws >> ciphered;
            if(fin.eof())
                break;
            if(ciphered == '\r' || ciphered == ' ' || ciphered == '\n')
            {
                fout << noskipws << ciphered;
            }
            else
            {
                ciphered = (unsigned char)(ciphered ^ keys[i % (ind + 1)]);
                fout << ciphered;
                i++;
            }
        }
        fin.close();
        fout.close();*/
    int stat[256];
    finS.open(fileOut, ios::binary);
    if (finS.is_open())
    {
        /*cout << "\"Out\" is opened!\n";*/
    }
    else
    {
        cout << "File opening error!\n\n";
        system("pause");
        return 0;
    }
    for (int i = 0; i < 256; i++)
    {
        stat[i] = 0;
    }
    unsigned char s_symb;
    cout << "Введите исследуемый символ.\n";
    cin >> s_symb;
    cout << endl << endl;
    fin.open(fileIn, ios::binary);
    fin.seekg(0, ios_base::beg);
    fin.close();
    fin.open(fileIn, ios::binary);
    ciphered = NULL;
    unsigned char chin;
    while (true)
    {
        fin >> chin;

        if (fin.eof())
            break;
        finS >> ciphered;
        if (chin == s_symb)
        {
            stat[ciphered]++;
        }
    }
    for (int i = 0; i < 256; i++)
    {
        cout << left << setw(4) << stat[i] << "";
        if ((i + 1) % 16 == 0) cout << endl;
    }
    fin.close();
    finS.close();
    fin.open(fileOut);
    fin.seekg(0, ios_base::beg);
    fin.close();
    fin.open(fileOut);
    fout.open(fileDecoded);
    i = 0;
    while (i < size)
    {
        fin >> noskipws >> ciphered;
        ciphered = (unsigned char)(ciphered ^ keys[i % (ind + 1)]);
        fout << ciphered;
        i++;
    }
    fin.close();
    fout.close();
    system("pause");
    return 0;

}