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Print all possible words that a phone number can present (C++, recursive)

int const PHONE_NUMBER_LENGTH = 3;

void PrintKeypadWords(int phoneNum [])

{

    char result[PHONE_NUMBER_LENGTH];

    DoPrintKeypadWords(phoneNum, 0, result);

}

void DoPrintKeypadWords(int phoneNum [], int currDigit, char result[])

{

    if (currDigit == PHONE_NUMBER_LENGTH)

    {

        result[PHONE_NUMBER_LENGTH] = '\0';

        std::cout << result << "\n";

        return;

    }

    for (int i = 1; i <= 3; i++)

    {

        result[currDigit] = GetCharKey(phoneNum[currDigit], i);

        DoPrintKeypadWords(phoneNum, currDigit + 1, result);

        if (phoneNum[currDigit] == 0 || phoneNum[currDigit] == 1)

        {

            return;

        }

    }

}

Test:

    int phoneNum[PHONE_NUMBER_LENGTH] = {4,8,2};

    PrintKeypadWords(phoneNum);