You are given an array A of length N and an array B of length N-1.
You need to output array where items alternates:
A[0], B[0], A[1], B[1], ..., B[N-2], A[N-1]
Restrictions:
N>0
Type of items is not specified, but code should work at least for unsigned integers.
Sample input:
A = [1,2,3,4]
B = [7,8,9]
Sample output:
[1,7,2,8,3,9,4]
Edge case input:
A = ['Hello, world']
B = []
Edge case output:
['Hello, world']
This question is a simplified version of Zip uneven lists.
Expects (A,B) and returns a new array.
-2 bytes if the integers are guaranteed to be positive, in which case this is identical to my answer to this closely related challenge.
f=([v,...a],b)=>1/v?[v,...f(b,a)]:a
Expects (A)(B). Outputs by modifying A.
a=>b=>b.map((v,i)=>a.splice(i-~i,0,v))
żẎ
I don't think there's a built-in directly for this...? Interleaving returns a 2D list and then we flatten it by one level (so even if either list is more than depth 1, this should be correct).
O#$`\d+(?<=((,)|.)+)
$#2
¶
,
Try it online! Takes two comma separated lists of unsigned integers as input. Explanation:
O#$`\d+(?<=((,)|.)+)
$#2
Sort each value by the number of preceding commas in its line.
¶
,
Join the two lists together.
ＵＭθ⮌ιＷ§θⅉ⟦Ｉ⊟ι
Try it online! Takes input as a pair of lists. Explanation: Same as my answer to the duplicate challenge.
ＵＭθ⮌ι
Reverse each of the two lists.
Ｗ§θⅉ
Cyclically index the lists according to the number of values already output and repeat until that list is empty.
⟦Ｉ⊟ι
Output the "next" value from that list on its own line.
(a:x)!b=a:b!x
a!_=a
-4 bytes thanks to Wheat Wizard
Defines an infix function ! (thanks to Wheat Wizard for this optimization) that returns [a[0], ...] (swapping arguments, so next we get [b[0], ...] which is followed by [a[1], ...], etc.) or if b is empty, just a.
fun f[]a=a|f(a::x)b=a::f b x
f=(a,b)=>b?a[to1]+f(b,a[1to]):a
f an infix function, and you can save a byte by swapping your cases: 25 bytes
\$\endgroup\$
Nalways be at least 2? Please add test cases to cover those possibilities, if applicable \$\endgroup\$