时间旅行者在这里
List_of_list =[([z for z in range(x-2,x+1) if z >= 0],y) for y in range(10) for x in range(10)]
这应该可以解决问题。输出是这样的:
[([0], 0), ([0, 1], 0), ([0, 1, 2], 0), ([1, 2, 3], 0), ([2, 3, 4], 0), ([3, 4, 5], 0), ([4, 5, 6], 0), ([5, 6, 7], 0), ([6, 7, 8], 0), ([7, 8, 9], 0), ([0], 1), ([0, 1], 1), ([0, 1, 2], 1), ([1, 2, 3], 1), ([2, 3, 4], 1), ([3, 4, 5], 1), ([4, 5, 6], 1), ([5, 6, 7], 1), ([6, 7, 8], 1), ([7, 8, 9], 1), ([0], 2), ([0, 1], 2), ([0, 1, 2], 2), ([1, 2, 3], 2), ([2, 3, 4], 2), ([3, 4, 5], 2), ([4, 5, 6], 2), ([5, 6, 7], 2), ([6, 7, 8], 2), ([7, 8, 9], 2), ([0], 3), ([0, 1], 3), ([0, 1, 2], 3), ([1, 2, 3], 3), ([2, 3, 4], 3), ([3, 4, 5], 3), ([4, 5, 6], 3), ([5, 6, 7], 3), ([6, 7, 8], 3), ([7, 8, 9], 3), ([0], 4), ([0, 1], 4), ([0, 1, 2], 4), ([1, 2, 3], 4), ([2, 3, 4], 4), ([3, 4, 5], 4), ([4, 5, 6], 4), ([5, 6, 7], 4), ([6, 7, 8], 4), ([7, 8, 9], 4), ([0], 5), ([0, 1], 5), ([0, 1, 2], 5), ([1, 2, 3], 5), ([2, 3, 4], 5), ([3, 4, 5], 5), ([4, 5, 6], 5), ([5, 6, 7], 5), ([6, 7, 8], 5), ([7, 8, 9], 5), ([0], 6), ([0, 1], 6), ([0, 1, 2], 6), ([1, 2, 3], 6), ([2, 3, 4], 6), ([3, 4, 5], 6), ([4, 5, 6], 6), ([5, 6, 7], 6), ([6, 7, 8], 6), ([7, 8, 9], 6), ([0], 7), ([0, 1], 7), ([0, 1, 2], 7), ([1, 2, 3], 7), ([2, 3, 4], 7), ([3, 4, 5], 7), ([4, 5, 6], 7), ([5, 6, 7], 7), ([6, 7, 8], 7), ([7, 8, 9], 7), ([0], 8), ([0, 1], 8), ([0, 1, 2], 8), ([1, 2, 3], 8), ([2, 3, 4], 8), ([3, 4, 5], 8), ([4, 5, 6], 8), ([5, 6, 7], 8), ([6, 7, 8], 8), ([7, 8, 9], 8), ([0], 9), ([0, 1], 9), ([0, 1, 2], 9), ([1, 2, 3], 9), ([2, 3, 4], 9), ([3, 4, 5], 9), ([4, 5, 6], 9), ([5, 6, 7], 9), ([6, 7, 8], 9), ([7, 8, 9], 9)]
这是通过列表理解完成的(这使得通过一行代码循环列表中的元素成为可能)。这段代码背后的逻辑如下:
(1) for x in range(10) 和 for y in range(10) 用于列表内的两个独立循环
(2) (a list, y) 是循环的总称,这也是为什么在(1)中放在两个for之前
(3) (2)中列表的长度不能超过3,并且列表依赖于x,所以
[z for z in range(x-2,x+1)]
用来
(4) 因为 z 从零开始,但是 range(x-2,x+1) 从 -2 开始,这不是我们想要的,所以如果 z >= 0 的条件语句放在 ( 2)
[z for z in range(x-2,x+1) if z >= 0]