00006

力扣 59 螺旋矩阵

class Solution(object):
    def generateMatrix(self, n):
        k = 0 
        x = 1
        matrix = [[0 for _ in range(n)] for _ in range(n)]
        mid = n // 2
        startx = 0
        starty = 0
        right = n - 1
        down = n - 1
        while k < mid:
            for i in range(startx, right + 1):
                matrix[startx][i] = x 
                x += 1
            for i in range(starty + 1, down + 1):
                matrix[i][right] = x
                x += 1
            for i in range(right - 1, startx - 1, -1):
                matrix[down][i] = x
                x += 1
            for i in range(down - 1, starty  , -1):
                matrix[i][startx] = x
                x += 1
            startx += 1
            starty += 1
            k += 1
            right -= 1
            down -= 1
        if n % 2 != 0:
            matrix[mid][mid] = x
        return matrix