#include <iostream>
using namespace std;

std::string encryptDecrypt(const std::string& toEncrypt)
{
    char key[9] = { '£', '£', '3', '4', '5', '6', '7', '8', '9' };
    std::string output = toEncrypt;
    for (int i = 0; i < toEncrypt.size(); i++)
        output[i] = toEncrypt[i] ^ key[i % (sizeof(key) / sizeof(char))];

    return output;
}

int main() {
	std::cout << encryptDecrypt("test") << std::endl;
	return 0;
}