leetcode刷题-59螺旋矩阵2

题目

给定一个正整数 n，生成一个包含 1 到 n^2 所有元素，且元素按顺时针顺序螺旋排列的正方形矩阵。

思路

与螺旋矩阵题完全一致

实现

class Solution:
    def generateMatrix(self, n: int) -> List[List[int]]:
        result = [[0 for _ in range(n)]for _ in range(n)]
        idx = 1
        left, right, top, bottom = 0, n - 1, 0, n - 1
        while left <= right and top <= bottom:
            for column in range(left, right + 1):
                result[top][column] = idx 
                idx += 1
            for row in range(top + 1, bottom + 1):
                result[row][right] = idx
                idx += 1
            if left < right and top < bottom:
                for column in range(right - 1, left, -1):
                    result[bottom][column] = idx
                    idx += 1
                for row in range(bottom, top, -1):
                    result[row][left] = idx
                    idx += 1
            left, right, top, bottom = left + 1, right - 1, top + 1, bottom - 1
        return result