___2

#include <iostream>
#include <vector>
#include <string>

using namespace std;

uint32_t cShiftR(uint32_t number)
{
    uint32_t mask = 0b111;
    return (number >> 3) | ((number & mask) << 29);
}

uint32_t cShiftL(uint32_t number)
{
    uint32_t mask = 0b111;
    mask <<= 29;
    return (number << 3) | ((number & mask) >> 29);
}


void decode(vector<uint32_t> data)
{
    int key;
    cout << "Enter key: ";
    cin >> key;

    if (data.size() == 0) {
        string str;
        cin.ignore();
        getline(cin, str);

        if (str.size() % 4 != 0) {
            cout << "Wrong string" << endl;
            return;
        }

        int length = str.size() / 4;
        data = vector<uint32_t>(length, 0);
        for (int i = 0; i < length * 4; i++) {
            data[i / 4] |= str[i] << 8 * (i % 4);
        }
    }

    int length = data.size();
    srand(key);
    for (int i = 0; i < length; i++) {
        uint32_t gamma = (rand() << 16) | rand();
        data[i] = cShiftR(data[i]) ^ gamma;
    }

    cout << "Decoded: ";
    for (int i = 0; i < length; i++)
        for (int j = 0; j < 4; j++) {
            char c = (char)(data[i] >> 8 * j);
            if (c != '\12')
                cout << c;
        }
    cout << endl;
}

void encode()
{
    int key;
    cout << "Enter key: ";
    cin >> key;

    string str;
    cout << "Enter string: ";
    cin.ignore();
    getline(cin, str);

    int length = str.size() / 4 + (str.size() % 4 != 0);
    vector<uint32_t> encoded(length, 0);
    for (int i = 0; i < length * 4; i++) {
        char c = ((str.size() > i) ? str[i] : '\12');
        encoded[i / 4] |= c << 8 * (i % 4);
    }

    srand(key);
    for (int i = 0; i < length; i++) {
        uint32_t gamma = (rand() << 16) | rand();
        encoded[i] = cShiftL(encoded[i] ^ gamma);
    }

    cout << "Encoded: ";
    for (int i = 0; i < length; i++)
        for (int j = 0; j < 4; j++)
            cout << (char)(encoded[i] >> 8 * j);
    cout << endl;

    decode(encoded);
}

int main()
{
    cout << "Encode (0) or decode (1): ";
    int state;
    cin >> state;
    if (state == 0) {
        encode();
    } else {
        decode({});
    }

    return 0;
}