[Python] 16939번 2×2×2 큐브

https://www.acmicpc.net/problem/16939

16939번: 2×2×2 큐브

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22/11/10

 

 

전형적인 구현 문제로, 큐브의 움직임을 따라가며 차근차근 구현하면 맞을 수 있는 문제이다.

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문제 접근 방식:

 

 

아래 그림을 보자.

출처: https://dm19sky.tistory.com/264

2*2*2 큐브에서 나올 수 있는 모든 회전들을 기호로 표현한 것으로, 총 12가지가 있다.

 

나는 5678이 새겨진 면을 맨 윗면으로 고정시켜놓고, 저렇게 한 번 회전시키는 것을 각각의 함수로 구현하였다.

 

다시 말해, 총 12가지의 함수를 구현한 것이다.

 

이 함수는 큐브 리스트를 입력받아 회전된 큐브 리스트를 반환하는 함수이다.

 

 

또 한 가지 함수, is_solved를 구현했는데, 이는 큐브 리스트를 입력받아 현재 모든 면이 각각 전부 완벽하게 맞춰져 있는가를 확인하는 함수로, 한 면은 4를 기준으로 끊겨있으므로 이를 이용하여 구현하였다.

 

 

12가지 함수와 위의 함수를 이용하여, 12가지 함수를 통해 나온 큐브 리스트들, 즉, 한 번씩 돌린 큐브 리스트들이 완벽하게 맞춰져 있는지 판단하는 check_rotate_once함수를 구현했다.

 

이 함수는 만약 완벽하게 맞춰져 있는 큐브가 존재하면 True를, 아니면 False를 반환하는 함수이다.

 

 

주어진 전개도를 이용하여 3차원 큐브를 가상으로 돌린다고 생각하고 구현하였다.

 

자세한 내용은 코드를 통해 확인하는 것이 좋을 것이다.

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아래는 내가 위의 접근 방식과 같이 작성한 파이썬 코드이다. 더보기를 누르면 확인할 수 있다.

# 16939번 2×2×2 큐브
# 구현
'''
접근 방법:
5678이 그려진 면이 윗면이라고 생각하고 돌리자.
'''
def is_solved(cube):
    for i in range(6):
        one_side = set()
        for j in range(1, 5):
            one_side.add(cube[4*i+j])
        if len(one_side) > 1:
            return False
    return True
def R(cube):
    two, four = cube[2], cube[4]
    six, eight = cube[6], cube[8]
    ten, twelve = cube[10], cube[12]
    twentyone, twentythree = cube[21], cube[23]
    cube[2], cube[4] = six, eight
    cube[6], cube[8] = ten, twelve
    cube[10], cube[12] = twentythree, twentyone
    cube[21], cube[23] = four, two
    cube[17], cube[18], cube[19], cube[20] = cube[19], cube[17], cube[20], cube[18]
    return cube
def r(cube):
    two, four = cube[2], cube[4]
    six, eight = cube[6], cube[8]
    ten, twelve = cube[10], cube[12]
    twentyone, twentythree = cube[21], cube[23]
    cube[2], cube[4] = twentythree, twentyone
    cube[6], cube[8] = two, four
    cube[10], cube[12] = six, eight
    cube[21], cube[23] = twelve, ten
    cube[17], cube[18], cube[19], cube[20] = cube[18], cube[20], cube[17], cube[19]
    return cube
def L(cube):
    one, three = cube[1], cube[3]
    five, seven = cube[5], cube[7]
    nine, eleven = cube[9], cube[11]
    twentytwo, twentyfour = cube[22], cube[24]
    cube[1], cube[3] = twentyfour, twentytwo
    cube[5], cube[7] = one, three
    cube[9], cube[11] = five, seven
    cube[22], cube[24] = eleven, nine
    cube[13], cube[14], cube[15], cube[16] = cube[15], cube[13], cube[16], cube[14]
    return cube
def l(cube):
    one, three = cube[1], cube[3]
    five, seven = cube[5], cube[7]
    nine, eleven = cube[9], cube[11]
    twentytwo, twentyfour = cube[22], cube[24]
    cube[1], cube[3] = five, seven
    cube[5], cube[7] = nine, eleven
    cube[9], cube[11] = twentyfour, twentytwo
    cube[22], cube[24] = three, one
    cube[13], cube[14], cube[15], cube[16] = cube[14], cube[16], cube[13], cube[15]
    return cube
def B(cube):
    five, six = cube[5], cube[6]
    thirteen, fourteen = cube[13], cube[14]
    seventeen, eighteen = cube[17], cube[18]
    twentyone, twentytwo = cube[21], cube[22]
    cube[5], cube[6] = seventeen, eighteen
    cube[13], cube[14] = five, six
    cube[21], cube[22] = thirteen, fourteen
    cube[17], cube[18] = twentyone, twentytwo
    cube[1], cube[2], cube[3], cube[4] = cube[3], cube[1], cube[4], cube[2]
    return cube
def b(cube):
    five, six = cube[5], cube[6]
    thirteen, fourteen = cube[13], cube[14]
    seventeen, eighteen = cube[17], cube[18]
    twentyone, twentytwo = cube[21], cube[22]
    cube[5], cube[6] = thirteen, fourteen
    cube[13], cube[14] = twentyone, twentytwo
    cube[21], cube[22] = seventeen, eighteen
    cube[17], cube[18] = five, six
    cube[1], cube[2], cube[3], cube[4] = cube[2], cube[4], cube[1], cube[3]
    return cube
def F(cube):
    seven, eight = cube[7], cube[8]
    fifteen, sixteen = cube[15], cube[16]
    nineteen, twenty = cube[19], cube[20]
    twentythree, twentyfour = cube[23], cube[24]
    cube[7], cube[8] = fifteen, sixteen
    cube[15], cube[16] = twentythree, twentyfour
    cube[19], cube[20] = seven, eight
    cube[23], cube[24] = nineteen, twenty
    cube[9], cube[10], cube[11], cube[12] = cube[11], cube[9], cube[12], cube[10]
    return cube
def f(cube):
    seven, eight = cube[7], cube[8]
    fifteen, sixteen = cube[15], cube[16]
    nineteen, twenty = cube[19], cube[20]
    twentythree, twentyfour = cube[23], cube[24]
    cube[7], cube[8] = nineteen, twenty
    cube[15], cube[16] = seven, eight
    cube[19], cube[20] = twentythree, twentyfour
    cube[23], cube[24] = fifteen, sixteen
    cube[9], cube[10], cube[11], cube[12] = cube[10], cube[12], cube[9], cube[11]
    return cube    
def D(cube):
    one, two = cube[1], cube[2]
    eleven, twelve = cube[11], cube[12]
    thirteen, fifteen = cube[13], cube[15]
    eighteen, twenty = cube[18], cube[20]
    cube[1], cube[2] = eighteen, twenty
    cube[11], cube[12] = thirteen, fifteen
    cube[13], cube[15] = two, one
    cube[18], cube[20] = twelve, eleven
    cube[21], cube[22], cube[23], cube[24] = cube[23], cube[21], cube[24], cube[22]
    return cube
def d(cube):
    one, two = cube[1], cube[2]
    eleven, twelve = cube[11], cube[12]
    thirteen, fifteen = cube[13], cube[15]
    eighteen, twenty = cube[18], cube[20]
    cube[1], cube[2] = fifteen, thirteen
    cube[11], cube[12] = twenty, eighteen
    cube[13], cube[15] = eleven, twelve
    cube[18], cube[20] = one, two
    cube[21], cube[22], cube[23], cube[24] = cube[22], cube[24], cube[21], cube[23]
    return cube
def U(cube):
    three, four = cube[3], cube[4]
    nine, ten = cube[9], cube[10]
    fourteen, sixteen = cube[14], cube[16]
    seventeen, nineteen = cube[17], cube[19]
    cube[3], cube[4] = sixteen, fourteen
    cube[9], cube[10] = nineteen, seventeen
    cube[14], cube[16] = nine, ten
    cube[17], cube[19] = three, four
    cube[5], cube[6], cube[7], cube[8] = cube[7], cube[5], cube[8], cube[6]
    return cube
def u(cube):
    three, four = cube[3], cube[4]
    nine, ten = cube[9], cube[10]
    fourteen, sixteen = cube[14], cube[16]
    seventeen, nineteen = cube[17], cube[19]
    cube[3], cube[4] = seventeen, nineteen
    cube[9], cube[10] = fourteen, sixteen
    cube[14], cube[16] = four, three
    cube[17], cube[19] = ten, nine
    cube[5], cube[6], cube[7], cube[8] = cube[6], cube[8], cube[5], cube[7]
    return cube
def check_rotate_once(cube):
    UP, up, DOWN, down, FRONT, front = U(cube[:]), u(cube[:]), D(cube[:]), d(cube[:]), F(cube[:]), f(cube[:])
    BACK, back, LEFT, left, RIGHT, right = B(cube[:]), b(cube[:]), L(cube[:]), l(cube[:]), R(cube[:]), r(cube[:])
    cube_list = [UP, up, DOWN, down, FRONT, front, BACK, back, LEFT, left, RIGHT, right]
    for rotated_cube in cube_list:
        if is_solved(rotated_cube):
            return True
    else:
        return False
CUBE = [0] + list(map(int, input().split()))
print(1 if check_rotate_once(CUBE) else 0)