Alguém pode me ajudar a encontrar casos de teste nos quais meu código não funcione?

//It fills a deck with unrepeated elements and returns the number of distinct elements
int readDeck(int deck[], int lenght)
{
    int aux, k = 0, i;

    for (i = 0; i < lenght; i++)
    {
        scanf("%d", &aux);
        if (k == 0)
        {
            deck[0] = aux;
            k++;
        }
        else if (deck[k - 1] != aux)
        {
            deck[k] = aux;
            k++;
        }
    }
    return k;
}

//It calculates the size of the intersection between two vectors
int sizeIntersection(int deckA[], int deckB[], int elementsA, int elementsB)
{
    int i, k, sair, numIntersections = 0;

    for (i = 0; i < elementsA; i++)
    {
        sair = 1;
        while (sair && k < elementsB)
        {
            if (deckA[i] == deckB[k])
            {
                numIntersections = numIntersections + 1;
                sair = 0;
            }
            else if (deckA[i] > deckB[k])
                k++;
            else
                sair = 0;
        }
    }

    return numIntersections;
}

int  main()
{
    int numberOfCardsA, numberOfCardsB;
    int distinctElementsA, distinctElementsB, intersection;
    int deckA[100000], deckB[100000];
    int aux, i;

    scanf("%d %d", &numberOfCardsA, &numberOfCardsB);

    while (numberOfCardsA != 0 && numberOfCardsB != 0)
    {
              distinctElementsA = readDeck(deckA, numberOfCardsA);
              distinctElementsB = readDeck(deckB, numberOfCardsB);
              intersection = sizeIntersection(deckA, deckB, distinctElementsA, distinctElementsB);

              //The  number of possible card exchanges is equal to the number of cards of the
              // smaller deck minus the magnitude of the intersection between the two decks.

              if (distinctElementsA >= distinctElementsB)
              {
                        if (distinctElementsB - intersection >= 0)
                                  printf("%d\n", distinctElementsB - intersection);
                        else
                                  printf("0\n");
              }
              else
              {
                      if (distinctElementsA - intersection >= 0)
                                printf("%d\n", distinctElementsA - intersection);
                      else
                                printf("0\n");
              }

              scanf("%d %d", &numberOfCardsA, &numberOfCardsB);
    }
    return 0;
 }