Which of the following 5  implementations could not be used for getFrequency?

public int getFrequencyOf(T anEntry)
{
  int i = 0;
  int count = 0;
  while(anEntry.equals(contents[i]))
  {
    i++;
    count++;
  }
  return numberOfEntries - count;
}

• public int getFrequencyOf(T anEntry)
  {
    int count = 0;
    for(int i = 0; i < numberOfEntries; i++)
    {
      if(anEntry.equals(contents[i]))
      {
        count++;
      }
    }
    return count;
  }

• public int getFrequencyOf(T anEntry)
  {
    int count = 0;
    for(int i = numberOfEntries - 1; i >= 0; i--)
    {
      if(anEntry.equals(contents[i]))
      {
        count++;
      }
    }
    return count;
  }

• public int getFrequencyOf(T anEntry)
  {
    int i = 0;
    int count = 0;
    while( i < numberOfEntries)
    {
      if(anEntry.equals(contents[i]))
      {
        count++;
      }
      i++;
    }
    return count;
  }

• public int getFrequencyOf(T anEntry)
  {
    int count = 0;
    for(int i = numberOfEntries - 1; i > -1; i--)
    {
      if(anEntry.equals(contents[i]))
      {
        count++;
      }
    }
    return count;
  }