[프로그래머스] 행렬 테두리 회전하기

 

 

 

출처: 프로그래머스 코딩 테스트 연습, https://programmers.co.kr/learn/challenges

 

 

 

 

 

머리로는 뭔가 할 수 있을 듯 말듯한데

 

결국 구글의 도움을 받아야 했음

 

def solution(rows, columns, queries):
    answer = []
    box = []
    for i in range(rows):
        row = []
        for j in range(columns):
            row.append(columns * i + j + 1)
        box.append(row)
    for querie in queries:
        행1, 열1, 행2, 열2 = querie
        
        행1 -= 1; 열1 -= 1; 행2 -= 1; 열2 -= 1
        tmp = box[행1][열1]
        small = tmp
        # left
        for i in range(행1 + 1, 행2 + 1):
            box[i-1][열1] = box[i][열1]
            small = min(small, box[i][열1])
        # bottom
        for i in range(열1 + 1, 열2 + 1):
            box[행2][i-1] = box[행2][i]
            small = min(small, box[행2][i])
        # right
        for i in range(행2 - 1, 행1 - 1, -1):
            box[i+1][열2] = box[i][열2]
            small = min(small, box[i][열2])
        # top
        for i in range(열2 - 1, 열1 - 1, -1):
            box[행1][i+1] = box[행1][i]
            small = min(small, box[행1][i])
            
        box[행1][열1+1] = tmp
        answer.append(small)
    return answer

 

참고:https://latte-is-horse.tistory.com/146

[프로그래머스 lv2] 행렬 테두리 회전하기 (파이썬)

 

 

더 좋은 코드를 발견해서 달아 놓음

 

def rotate(x1, y1, x2, y2, graph, answer):
    # 오른쪽, 아래, 왼쪽, 위 순
    dx = 0, 1, 0, -1
    dy = 1, 0, -1, 0
    d, x, y, tmp = 0, x1, y1, 10000
    min_val = 10000
    while d < 4:
        nx = x + dx[d]
        ny = y + dy[d]
        min_val = min(min_val, graph[x][y])
        # 범위 안인 경우
        if x1 <= nx <= x2 and y1 <= ny <= y2:
            graph[x][y], tmp = tmp, graph[x][y]
            x, y = nx, ny
        else:
            d += 1
    graph[x1][y1] = tmp
    answer.append(min_val)


def solution(rows, columns, queries):
    answer = []
    graph = [[i + 1 for i in range(j * columns, (j + 1) * columns)] for j in range(rows)]
    for query in queries:
        x1, y1, x2, y2 = map(int, query)
        rotate(x1 - 1, y1 - 1, x2 - 1, y2 - 1, graph, answer)
    return answer

출처: https://intrepidgeeks.com/tutorial/rotate-programmer-matrix-border-python