If I have a list
List<int> mylist = new List<int>();
mylist.Add(15);
mylist.Add(15);
mylist.Add(10);
mylist.Add(10);
mylist.Add(10);
If you want Count() which is equal to "10" Give me the number 3
It sounds like you probably just want to use LINQ:
int target = 10; // Or whatever
int count = myList.Count(x => x == target);
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