Day 7: Bridge Repair

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FAQ

  • TunaCowboy@lemmy.world
    0·
    3 months ago

    python

    45s on my machine for first shot, trying to break my will to brute force 😅. I’ll try improving on it in a bit after I smoke another bowl and grab another drink.

    solution 
    from itertools import product
import re
import aoc

def ltr(e):
    r = int(e[0])
    for i in range(1, len(e), 2):
        o = e[i]
        n = int(e[i + 1])
        if o == '+':
            r += n
        elif o == '*':
            r *= n
        elif o == '||':
            r = int(f"{r}{n}")
    return r

def one():
    lines = aoc.get_lines(7)
    rs = []
    for l in lines:
        d = [int(x) for x in re.findall(r'\d+', l)]
        t = d[0]
        ns = d[1:]
        ops = list(product(['+', '*'], repeat=len(ns) - 1))
        for o in ops:
            e = str(ns[0])
            for i, op in enumerate(o):
                e += f" {op} {ns[i + 1]}"
            r = ltr(e.split())
            if r == t:
                rs.append(t)
                break
    print(sum(rs))

def two():
    lines = aoc.get_lines(7)
    rs = []
    for l in lines:
        d = [int(x) for x in re.findall(r'\d+', l)]
        t = d[0]
        ns = d[1:]
        ops = list(product(['+', '*', '||'], repeat=len(ns) - 1))
        for o in ops:
            e = str(ns[0])
            for i, op in enumerate(o):
                e += f" {op} {ns[i + 1]}"
            r = ltr(e.split())
            if r == t:
                rs.append(t)
                break
    print(sum(rs))

one()
two()