Search value from comma separated string List based on index using C# and VB.Net in ASP.Net

Hi Team,

How to search the list and take based on the index value in c#

List<slot> slots=new List<slot>();
slots.add(new slot{Ids="2,3,4,6,8,9,1"});
slots.add(new slot{Ids="10,11,12,13,1,7"});
slots.add(new slot{Ids="1,4,6,5,10,11,29,40,7"});

In above all the list have "1" but If I search with one then it should return the 3d list because of the index, so just need to compare the index also and need to take that one.

IF I search with "7" then it should return 2nd list

How to achieve this?