def parse(file): while True: a = file.readline() if not a: break b = file.readline() pr = file.readline() blank = file.readline() ax, ay = parse_numbers(a) bx, by = parse_numbers(b) px, py = parse_numbers(pr) yield ax,ay, bx,by, px,py import re def parse_numbers(s): return [int(x) for x in re.findall(r"\d+", s)] from fractions import Fraction as F import numpy def solve(file): total = 0 total2 = 0 records = list(parse(file)) for record in records: #print(record) ax, ay, bx, by, px, py = record # Part 1 # Solve the linear equation: # k_a ax + k_b * bx = px # k_a ay + k_b * by = py M = numpy.array([[ax, bx], [ay, by]]) V = numpy.array([px, py]) sol = numpy.linalg.solve(M,V) k1 = int(round(sol[0])) k2 = int(round(sol[1])) if k1*ax + k2*bx == px and k1*ay + k2*by == py: #print("yes", k1, k2) total += 3*k1 + k2 # Part 2 qx = px + 10000000000000 qy = py + 10000000000000 V2 = numpy.array([qx, qy]) sol = numpy.linalg.solve(M,V2) k1 = int(round(sol[0])) k2 = int(round(sol[1])) if k1*ax + k2*bx == qx and k1*ay + k2*by == qy: #print("yes2", k1, k2) total2 += 3*k1 + k2 print(total) print(total2) solve(open("sample1.in")) solve(open("input"))