Command

./perfect_hash.py -v --splitby=":" fruits.txt

fruits.txt

# fruit test data

  Apple      : 0
  Apricot    : 1
  Avocado    : 2
  Banana     : 3
  Blueberry  : 4
  Blackberry : 5

Execution Log

keys_file = 'fruits.txt'
Reading table from file `fruits.txt' to extract keys.
Reader options:
  comment: '#'
  splitby: ':'
  keycol: 1
Number os keys: 6
tmpl_file = None
outname = 'std'

NG = 7

Generating graphs NG = 7 .....
Generating graphs NG = 8 .....
Generating graphs NG = 9 ..
Acyclic graph found after 12 trials.
NG = 9
OK
Format options:
  width: 76
  indent: 4
  delimiter: ', '
# =======================================================================
# ================= Python code for perfect hash function ===============
# =======================================================================

G = [0, 0, 5, 5, 6, 2, 0, 4, 7]

def hash_f(key, T):
    return sum(ord(T[i % 10]) * ord(c) for i, c in enumerate(key)) % 9

def perfect_hash(key):
    return (G[hash_f(key, "aPUw6kzCOV")] +
            G[hash_f(key, "gfrifJM7cA")]) % 9

# ============================ Sanity check =============================

K = ["Apple", "Apricot", "Avocado", "Banana", "Blueberry", 
    "Blackberry"]
assert len(K) == 6

for h, k in enumerate(K):
    assert perfect_hash(k) == h