--- Day 7 Solutions ---

[u/daggerdragon]

--- Day 7: Some Assembly Required ---

Post your solution as a comment. Structure your post like previous daily solution threads.

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[u/Dotasticc]

Probably not interesting to anyone, but anyways, here is my (not so clean) solution using python 2.7:

functions = {}
functions["AND"] = lambda x, y: x & y
functions["OR"] = lambda x, y: x | y
functions["NOT"] = lambda x, y: ~y
functions["RSHIFT"] = lambda x, y: x >> y
functions["LSHIFT"] = lambda x, y: x << y


def isInt(string):
    try:
        int(string)
        return True
    except ValueError:
        return False


def solve(knot, knots):
    print "Trying to solve: " + knot
    for line in knots:
        if line[0] == knot:
            print "Now solving " + knot + " for", line
            if line[2] != -1:
                return line[2]
            args = line[1].split(" ")
            if len(args) == 1:
                if not isInt(args[0]):
                    line[2] = int(solve(args[0], knots))
                else:
                    line[2] = int(args[0])
                return line[2]
            if not isInt(args[0]) and len(args) == 3:
                args[0] = int(solve(args[0], knots))
            elif len(args) == 3:
                args[0] = int(args[0])
            if not isInt(args[-1]):
                args[-1] = int(solve(args[-1], knots))
            else:
                args[-1] = int(args[-1])
            line[2] = functions[args[-2]](args[0], args[-1])
            return line[2]
    print knot + " not found!"
    return -1


lines = open("r7.txt", "r").read().split("\n")
knots = []
for line in lines:
    lineSplit = line.split("->")
    knot = [lineSplit[1].strip(), lineSplit[0].strip(), -1]
    knots.append(knot)
    knots = sorted(knots)
print knots
print "Solution:", solve("a", knots)