for (let a of "abcdefg")
  for (let b of "abcdefg")
    for (let c of "abcdefg")
      for (let d of "abcdefg")
        for (let e of "abcdefg")
          for (let f of "abcdefg")
            for (let g of "abcdefg") {

let x = [..."abcdefg"]
while(true){
  x.sort(() => Math.random() - .5)

-- length 2: 1
-- length 3: 7
-- length 4: 4
-- length 7: 8
-- length 5:
--     contains all of 1's segments: 3
--     contains all of 4's segments that are not 1's: 5
--     otherwise: 2
-- length 6:
--     contains all of 1's and 5's segments: 9
--     contains all of 7's segments: 0
--     otherwise: 6

 on‿fo‿se‿ei ← masks⊏˜2‿4‿3‿7⊐˜+´¨masks # 1,4,7,8  # Part 1 idea
  si ← ⊑{(ei≢𝕩)∧ei≡on∨𝕩}¨⊸/masks                    # 6: 1 and 6 combined makes 8
  fi ← ⊑{(ei≢𝕩)∧1=+´si≠𝕩}¨⊸/masks                   # 5: single place difference with 6 and isn't 8
  ni ← ⊑{(si≢𝕩)∧(𝕩≡𝕩∨fo)∧1=+´ei≠𝕩}¨⊸/masks          # 9: not 6 and single place difference with 8
  ze ← ⊑(6=+´)¨⊸/masks(¬∘∊/⊣)ni‿si                  # 0: not 9 and not 6 and contains 6 segments
  tw ← ⊑masks/˜{(se≢𝕩)∧4=+´fi≠𝕩}¨masks              # 2: 2 places not common with 5 and isn't 7

from itertools import *

t = 0

for k in lines:
    a, b = k.split(" | ")
    do = ["abcefg", "cf", "acdeg", "acdfg", "bcdf", "abdfg", "abdefg", "acf", "abcdefg", "abcdfg"]
    req = set(do)
    for x in permutations("abcdefg"):
        m = {i: j for i, j in zip(x, "abcdefg")}
        r = {"".join(sorted(map(m.get, q))) for q in a.split()}
        if r == req:
            b = ["".join(sorted(map(m.get, q))) for q in b.split()]
            b = "".join(str(do.index(q)) for q in b)
            t += int(b)

with open('input', 'r') as file:
    lines = file.read().splitlines()
    total = 0
    for line in lines:
        mapping = {}
        signals, output = [x.split() for x in line.split(' | ')]
        signals = sorted(signals, key=len)
        mapping[1] = signals[0]
        mapping[7] = signals[1]
        mapping[4] = signals[2]
        mapping[8] = signals[9]
        l6 = signals[6:9]
        mapping[9] = next(x for x in l6 if set(mapping[4]).issubset(x))
        l6.remove(mapping[9])
        mapping[0] = next(x for x in l6 if set(mapping[7]).issubset(x))