C# Program to Find the Sum of a Sequence

Firstly, set a sequence.

List<int> myList = new List<int> { 1, 2, 3, 4 ,5};

Now find the sum using the Queryable Sum() method.

myList.AsQueryable().Sum();

Example

 Live Demo

using System;
using System.Linq;
using System.Collections.Generic;
public class Demo {
   public static void Main() {
      List<int> myList = new List<int> { 1, 2, 3, 4 ,5};
      Console.WriteLine("Sum of elements in a list...");
      foreach (int res in myList) {
         Console.WriteLine(res);
      }
      int sum = myList.AsQueryable().Sum();
      Console.WriteLine("Sum = {0}", sum);
   }
}

Output

Sum of elements in a list...
1
2
3
4
5
Sum = 15