59. Spiral Matrix II Leetcode Python

Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.


For example,
Given n = 3,


You should return the following matrix:
[
 [ 1, 2, 3 ],
 [ 8, 9, 4 ],
 [ 7, 6, 5 ]

]

这题的解法和spiral matrix1的解法一样，不同的是这个问题的行和列数都一样，所以在算的时候稍微简单一些。

代码如下：

class Solution:    # @return a list of lists of integer    def generateMatrix(self, n):        maxup=0        maxleft=0        maxright=n-1        maxdown=n-1        direction=0        matrix=[[0 for i in range(n)] for j in range(n)]        num=range(1,n*n+1)        iter=0        while True:            if direction==0:                for i in range(maxleft,maxright+1):                    matrix[maxup][i]=num[iter]                    iter+=1                maxup+=1            if direction==1:                for i in range(maxup,maxdown+1):                    matrix[i][maxright]=num[iter]                    iter+=1                maxright-=1            if direction==2:                for i in reversed(range(maxleft,maxright+1)):                    matrix[maxdown][i]=num[iter]                    iter+=1                maxdown-=1            if direction==3:                for i in reversed(range(maxup,maxdown+1)):                    matrix[i][maxleft]=num[iter]                    iter+=1                maxleft+=1            if maxleft>maxright or maxup>maxdown:                return matrix            direction=(direction+1)%4