fallout4.py

#!/usr/bin/env python3
"""

ROBCO Industries (TM) Password Recovery Tool
----
Next-generation hacking assistant for your RobCo Pip-Boy 3000.

> Words: seven peace broke small steal agree deity armed store empty codes brink
> 
> try: peace (6 matches)
> score? [likeness n or Ctrl-C] 1
> OK, updating constraints: {'peace': 1}
> 1 constraints, 6 words left
> 
> try: agree (3 matches)
> score? [likeness n or Ctrl-C] 1
> OK, updating constraints: {'peace': 1, 'agree': 1}
> 2 constraints, 3 words left
> 
> try: seven (1 matches)
> score? [likeness n or Ctrl-C] 0
> OK, updating constraints: {'peace': 1, 'agree': 1, 'seven': 0}
> 3 constraints, 1 words left
> 
> Password: broke

"""


import re

def sim(a, b):
    assert len(a) == len(b)
    return sum(1 for (ac, bc) in zip(a, b) if ac == bc)

def filter_words(words, constraints):
    return [w for w in words if all(sim(w, c[0]) == c[1] for c in constraints.items())]

def find_middle(words):
    results = []
    for w in words:
        sims = [(x, sim(w, x)) for x in words if x != w]
        sims = [s for s in sims if s[1] > 0]
        results.append((w, len(sims), sims))

    closest = min(results, key=lambda x:abs(x[1]-len(words)/2))
    return closest

def main():
    print()
    print("Welcome to ROBCO Industries (TM) Password Recovery Tool")
    print()

    print("Words: ", end="")
    words = input().lower()
    words = re.sub('[^a-z]', ' ', words)
    words = re.split(' +', words)
    print()

    constraints = {}
    while True:
        subset = filter_words(words, constraints)

        if len(subset) == 0:
            print("No words left, impossible constraints.")
            break

        if len(subset) == 1:
            print("Password: %s" % subset[0])
            break

        word, n_matches, matches = find_middle(subset)
        print("try: %s (%d matches)" % (word, n_matches))
        print("score? [likeness n or Ctrl-C] ", end="")
        likeness = int(input())
        constraints[word] = likeness
        subset = filter_words(words, constraints)
        print("OK, updating constraints: %r" % constraints)
        print("%d constraints, %d words left" % (len(constraints), len(subset)))
        print()

main()