char *resize(const char *str, size_t size, size_t new_size) {
    char *newStr = new char[new_size];
    for (int i = 0; i < min(size, new_size); ++i) {
        newStr[i] = str[i];
    }
    delete[] str;
    return newStr;
}

char *getline() {
    size_t size = 10;
    char *str = new char[size];
    size_t curLen = 0;
    char c;
    cin.get(c);
    while (true) {
        if (c == '\0'){
            if (curLen != 0) {
                break;
            }
            return nullptr; // не пашет если в конце непробельный или не \n и застревает
        }
        if (c == '\n') {
            break;
        }
        if (curLen == size - 1) {
            str = resize(str, size, size * 2);
            size *= 2;
        }
        str[curLen] = c;
        curLen++;
        cin.get(c);
    }
    str[curLen] = '\0';
    return str;
}