day_03b.py

#!/usr/bin/python3

import math
import sys


def GetWireCoordinatesList(input):
    init_x = 0
    init_y = 0
    wire = list()
    for inst in input:
        if inst[0] == "R":
            for inc in range(1, int(inst[1:]) + 1):
                init_x += 1
                wire.append((init_x, init_y))
        elif inst[0] == "U":
            for inc in range(1, int(inst[1:]) + 1):
                init_y += 1
                wire.append((init_x, init_y))
        elif inst[0] == "L":
            for inc in range(1, int(inst[1:]) + 1):
                init_x -= 1
                wire.append((init_x, init_y))
        elif inst[0] == "D":
            for inc in range(1, int(inst[1:]) + 1):
                init_y -= 1
                wire.append((init_x, init_y))
    return wire


def GetWireCoordinatesSet(input):
    init_x = 0
    init_y = 0
    wire = set()
    for inst in input:
        if inst[0] == "R":
            for inc in range(1, int(inst[1:]) + 1):
                init_x += 1
                wire.add((init_x, init_y))
        elif inst[0] == "U":
            for inc in range(1, int(inst[1:]) + 1):
                init_y += 1
                wire.add((init_x, init_y))
        elif inst[0] == "L":
            for inc in range(1, int(inst[1:]) + 1):
                init_x -= 1
                wire.add((init_x, init_y))
        elif inst[0] == "D":
            for inc in range(1, int(inst[1:]) + 1):
                init_y -= 1
                wire.add((init_x, init_y))
    return wire


def main():
    # Get input
    file_name = "../input/day_03_input"
    if len(sys.argv) > 1:
        file_name = sys.argv[1]
    file = open(file_name)
    input1 = file.readline().strip("\n").split(",")
    input2 = file.readline().strip("\n").split(",")

    # Solve
    listwire1 = GetWireCoordinatesList(input1)
    listwire2 = GetWireCoordinatesList(input2)
    setwire2 = GetWireCoordinatesSet(input2)

    man_dist = math.inf
    distance = math.inf
    for dist1, coor in enumerate(listwire1):
        if coor in setwire2:
            distance = min(distance, dist1 + listwire2.index(coor))
    distance = (
        distance + 2
    )  # the list does not account for the central port as a coordinate to remove an if statement from the find intersection step
    print(distance)
    return distance


if __name__ == "__main__":
    main()