백준 1604번 python 3 풀이

from fractions import Fraction
import sys
class Line:

    def __init__(self, param):
        self.ax = int(param[0])
        self.ay = int(param[1])
        self.bx = int(param[2])
        self.by = int(param[3])


        # ax + by = c
        self.a = self.by - self.ay
        self.b = self.ax - self.bx
        self.c = self.a * self.ax + self.b * self.ay


    # def debug(self):
        # print([self.a, self.b, self.c])


    def crossPoint(self, otherLine):

        de = self.a * otherLine.b - self.b * otherLine.a
        if de == 0:
            return False
        x = Fraction(self.c * otherLine.b - self.b * otherLine.c, de)
        y = Fraction(self.a * otherLine.c - self.c * otherLine.a, de)
        if (-10 < x and x < 10 and -10 < y and y < 10):
            return (x, y)
        else:
            return False
        if (x >= 10 or x <= -10):
            return False
        if (y >= 10 or y <= -10):
            return False
        print(x,y)
        return (x, y)

    def upperArea(self, point):
        return self.a * point[0] + self.b * point[1] - self.c >= 0

    def downArea(self, point):
        return self.a * point[0] + self.b * point[1] - self.c <= 0

    def inBox(self):

        # x = += 10, y += 10 같은 변태적인 경우 제외.
        # print(self.a, self.b, self.c)
        if self.a == 0:
            cb = Fraction(self.c) / Fraction(self.b)
            if cb >= 10 or cb <= -10:
                return False
        if self.b == 0:
            ca = Fraction(self.c) / Fraction(self.a)
            if ca >= 10 or ca <= -10:
                return False




        if (self.upperArea((-10, 10)) is True) and (self.upperArea((10, 10)) is True) and (self.upperArea((-10, -10)) is True) and (self.upperArea((10, -10)) is True):
            return False
        if (self.downArea((-10, 10)) is True) and (self.downArea((10, 10)) is True) and (self.downArea((-10, -10)) is True) and (self.downArea((10, -10)) is True):
            return False

        if (self.ax >= 10 and self.bx >= 10):
            return False
        if (self.ax <= -10 and self.bx <= -10):
            return False
        if (self.ay >= 10 and self.by >= 10):
            return False
        if (self.ay <= -10 and self.by <= -10):
            return False

        return True


def main():

    n = int(sys.stdin.readline())
    lines = []
    for i in range(0, n):
        a = sys.stdin.readline().split(' ')
        # print(a)
        line = Line(a)
        if line.inBox():
            lines.append(line)

    answer = 1
    for line in lines:
        answer += 1
        # if line.inBox():
            # print("in")
            # print(line.a,"x+", line.b,"y=", line.c)
            # print(line.ax, line.ay, line.bx, line.by)

    length = len(lines)
    for i in range(0, length):
        for j in range(i+1, length):
            line = lines[i]
            otherLine = lines[j]
            crossPoint = line.crossPoint(otherLine)
            if crossPoint != False:
                answer += 1
            # else:
                # print("a")
        # print(pointSet)


    print(answer)


main()

역대급 역겨운 문제였습니다.