2019-수학-가형-홀수-4

문제

2019-수학-가형-홀수-4

풀이

from random import randint
from sympy import Rational

def random_subset(s):
    out = set()
    for el in s:                                                                                                                    
        # random coin flip
        if randint(0, 1) == 0:
            out.add(el)
    return out


def Prob(S):
    return Rational(len(S), len(U))


def complement(S):
    # difference between a global universal set U and the given set a
    return U - S


def intersection(a,b):
    return set(a) & set(b)
U= set(range(1,7))
A={1,2}
Ac=complement(A)
Bnotfound = True;
while Bnotfound:
    B = random_subset(U)
    Bc = complement(B)
    if Prob(intersection(A, Bc)) == 0 and Prob(intersection(Ac, B))==Rational(1,6) :
        Bnotfound = False;
        print([B, Prob(B)])
        break
[{1, 2, 6}, 1/2]