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std::vector<std::string> take_words(std::string str) {
    std::vector<std::string> str_arr;
    unsigned int point_begin = 0;
    bool is_end=false;
    for (int i = point_begin; i < str.size(); i++) {
        if (is_end) {
            break;
        }
        if (str[point_begin] == ' ') {
            point_begin++;
            continue;
        }
        else if (str[point_begin] == '\0') {
            break;
        }
        str_arr.resize(str_arr.size() + 1);
        for (int j = point_begin; j < str.size(); j++) {
            if (str[j] == ' ') {
                point_begin = j + 1;
                break;
            }
            str_arr[str_arr.size() - 1] += str[j];
            if (j == str.size() - 1) {
                is_end = true;
            }
        }
    }
    return str_arr;
}