private int getBigramItemIndex(char carray[]) {
    long hashId = hash1(carray);
    int hash1 = (int) (hashId % PRIME_BIGRAM_LENGTH);
    int hash2 = hash2(carray) % PRIME_BIGRAM_LENGTH;
    if (hash1 < 0)
      hash1 = PRIME_BIGRAM_LENGTH + hash1;
    if (hash2 < 0)
      hash2 = PRIME_BIGRAM_LENGTH + hash2;
    int index = hash1;
    int i = 1;
    repeat++;
    while (bigramHashTable[index] != 0 && bigramHashTable[index] != hashId
        && i < PRIME_BIGRAM_LENGTH) {
      index = (hash1 + i * hash2) % PRIME_BIGRAM_LENGTH;
      i++;
      repeat++;
      if (i > max)
        max = i;
    }
    // System.out.println(i - 1);

    if (i < PRIME_BIGRAM_LENGTH && bigramHashTable[index] == hashId) {
      return index;
    } else
      return -1;
  }