Day 11 Part 1

import numpy as np
from functools import reduce

def manhattan_distance(a, b) -> int:
    return abs(a[0]-b[0])+abs(a[1]-b[1])

if __name__ == "__main__":

    DATA_FILE = "galaxy.txt"
    with open(DATA_FILE) as data_file:

        # read data in
        lines = data_file.readlines()

        # remove line endings
        lines = [l.strip() for l in lines]

        # split into chars - 2D array - to numpy
        lines = np.array([[c for c in x] for x in lines])

        # get col and row indices where all '.'
        rows_idx=np.array(np.where(np.all(lines == ".", axis=1))).flatten()
        cols_idx=np.array(np.where(np.all(lines == ".", axis=0))).flatten()

        # add extra '.' rows and cols
        lines=np.insert(lines, rows_idx, '.', axis=0)
        lines=np.insert(lines, cols_idx, '.', axis=1)

        # get indices of the galaxies
        galaxy_idx = np.transpose((lines == '#').nonzero())

        # iterate through galaxy and calc distance
        total_distance = reduce(lambda x,y: np.sum(x)+np.sum(y), [np.array([manhattan_distance(galaxy_idx[i], galaxy_idx[j]) for j in range(i+1, len(galaxy_idx))]) for i in range(len(galaxy_idx)-1)])

        # print the answer
        print(f"{total_distance}")