How to combine multiple lists with custom sequence
algorithm, c#, list
Solution
Not sure if there's a name. Merging? Splicing? But the code is easy.
var lists = new [] { list1, list2, list3 };
var combined = new List<string>(lists.Sum(l => l.Count));
for (var i = 0; i < lists.Max(l => l.Count); i++)
{
foreach (var list in lists)
{
if (i < list.Count)
combined.Add (list[i])
}
}
Problem
Not sure if there's a algorithm to describe this problem but are there any elegant methods to combine the list in a custom sequence. For example: ``` List<string> list1 = new List<string>(); List<string> list2 = new List<string>(); List<string> list3 = new List<string>(); list1.Add("a"); list1.Add("b"); list1.Add("c"); list2.Add("d"); list2.Add("e"); list2.Add("f"); list3.Add("g"); list3.Add("h"); list3.Add("i"); List<string> combined = new List<string>(); ``` I would like the contents of combined to contain a sequence as follows: ``` a //First record in list1 d //First record in list2 g //First record in list3 b //Second record in list1 e //Second record in list2 h //Second record in list3 c //Third record in list1 f //Third record in list2 i //Third record in list3 ``` The number of records in each list may not be equal. EDIT When the number of records in each list may not be equal i mean: ``` List<string> list1 = new List<string>(); List<string> list2 = new List<string>(); List<string> list3 = new List<string>(); list1.Add("a"); list2.Add("b"); list2.Add("c"); list3.Add("d"); list3.Add("e"); list3.Add("f"); List<string> combined = new List<string>(); ``` Expected results: ``` a //First record in list1 b //First record in list2 d //First record in list3 c //Second record in list2 e //Second record in list3 f //Third record in list3 ```