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List<T>.Reverse(int index, int count) method with example in C#

C# List<T>.Reverse(int index, int count) method: Here, we are going to learn about the Reverse(int index, int count) method of List with example.
Submitted by IncludeHelp, on March 15, 2019

C# List<T>.Reverse(int index, int count) Method

List<T>.Reverse(int index, int count) method is used to reverse the specified elements in the list.

Syntax:

    void List<T>.Reverse(int index, int count);

Parameter: It accepts two parameters 1) index – starting position from where we want to reverse the elements and 2) count – total number of elements from the index.

Return value: It returns nothing – it's returns type is void

Example:

    int list declaration:
    List<int> a = new List<int>();

    adding elements:
    a.Add(10);
    a.Add(20);
    a.Add(30);
    a.Add(40);
    a.Add(50);
    
    reversing elements:
    //reverse 3 list elements from index 1
    a.Reverse(1,3);
    
    Output:
    10 40 30 20 50

C# Example to reverse specified list elements using List<T>.Reverse(int index, int count) Method

using System;
using System.Text;
using System.Collections.Generic;

namespace Test
{
    class Program
    {
        static void printList(List<int> lst)
        {
            //printing elements
            foreach (int item in lst)
            {
                Console.Write(item + " ");
            }
            Console.WriteLine();
        }

        static void Main(string[] args)
        {
            //integer list
            List<int> a = new List<int>();

            //adding elements
            a.Add(10);
            a.Add(20);
            a.Add(30);
            a.Add(40);
            a.Add(50);

            if (a.Count > 0)
            {
                //print the list
                Console.WriteLine("list elements...");
                printList(a);
            }
            else
            {
                Console.WriteLine("list is empty");
            }

            //reverse 3 list elements from index 1
            a.Reverse(1,3);

            //list after reversing the elements
            if (a.Count > 0)
            {
                Console.WriteLine("list elements after reversing elements...");
                printList(a);
            }
            else
            {
                Console.WriteLine("list is empty");
            }

            //hit ENTER to exit
            Console.ReadLine();
        }
    }
}

Output

list elements...
10 20 30 40 50
list elements after reversing elements...
10 40 30 20 50