在数组内部合并数组

Question

我有这样一个数组:

a = [[1,2,3,4,5],[3,5,6,8,12,45],[3,2,1,5,7,9,10,11],[3,5,6,8,2,1,3,4,6]]

我想合并它的内部数组，使它们变成:

a = [[1,2,3,4,5,3,5,6,8,12,45],[3,2,1,5,7,9,10,11,3,5,6,8,2,1,3,4,6]]

我该怎么做?

Answer 1

你需要做

 a = [
     [1, 2, 3, 4, 5],
     [3, 5, 6, 8, 12, 45],
     [3, 2, 1, 5, 7, 9, 10, 11],
     [3, 5, 6, 8, 2, 1, 3, 4, 6]
 ]
a.each_slice(2).map(&:flatten)
# => [
#     [1, 2, 3, 4, 5, 3, 5, 6, 8, 12, 45],
#     [3, 2, 1, 5, 7, 9, 10, 11, 3, 5, 6, 8, 2, 1, 3, 4, 6]
# ]

读取方法each_slice(n)

为n元素的每个切片迭代给定的块。如果没有给出块，返回一个枚举数。