How do I add two lists in Linq so addedList[x] = listOne[x] + listTwo[x]?

Question

I want to add two lists of a numeric type such that addedList[x] = listOne[x] + listTwo[x]

The output of the list needs to be a Generic.IEnumerable that I can use i

Answer 1

var res = list.Concat(list1); 

concatenates two lists, including eventual duplicates.

var res = list.Union(list1);

concatenates two lists, providing a result without duplicates.