螺旋矩阵
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 ]
]
看博客园有人面试碰到过这个问题，长篇大论看得我头晕。跑去leetcode讨论区，看来看去还是我python大法牛逼，四行就搞定了你敢信。。
| 1 | 2 | 3 |
| 8 | 9 | 4 |
| 7 6 | 5 |
如果看不明白的话，大致过程像上面这样，颜色相同表示在同一步骤里面执行
>>> def generateMatrix(n):
... A, low = [], n*n+1
... while low > 1:
... low, high = low - len(A), low
... A = [list(range(low, high))] + list(zip(*A[::-1])) # python3.3 语法 与2.7会有差别
... print(A)
... return A
...
>>> generateMatrix(1)
[[]]
[[1]]
[[1]]
>>> generateMatrix(2)
[[]]
[[4]]
[[3],
(4,)]
[[1, 2],
(4, 3)]
[[1, 2], (4, 3)]
>>> generateMatrix(3)
[[]]
[[9]]
[[8],
(9,)]
[[6, 7],
(9, 8)]
[[4, 5],
(9, 6),
(8, 7)]
[[1, 2, 3],
(8, 9, 4),
(7, 6, 5)]
[[1, 2, 3], (8, 9, 4), (7, 6, 5)]