Helpers.cs

using System.Collections.Generic;
using DataStructures.Lists;

namespace Algorithms.Common;

public static class Helpers
{
    /// <summary>
    /// Swaps two values in an IList<T> collection given their indexes.
    /// </summary>
    public static void Swap<T>(this IList<T> list, int firstIndex, int secondIndex)
    {
        if (list.Count < 2 || firstIndex == secondIndex)   //This check is not required but Partition function may make many calls so its for perf reason
            return;

        var temp = list[firstIndex];
        list[firstIndex] = list[secondIndex];
        list[secondIndex] = temp;
    }

    /// <summary>
    /// Swaps two values in an ArrayList<T> collection given their indexes.
    /// </summary>
    public static void Swap<T>(this ArrayList<T> list, int firstIndex, int secondIndex)
    {
        if (list.Count < 2 || firstIndex == secondIndex)   //This check is not required but Partition function may make many calls so its for perf reason
            return;

        var temp = list[firstIndex];
        list[firstIndex] = list[secondIndex];
        list[secondIndex] = temp;
    }

    /// <summary>
    /// Populates a collection with a specific value.
    /// </summary>
    public static void Populate<T>(this IList<T> collection, T value)
    {
        if (collection == null)
            return;

        for (int i = 0; i < collection.Count; i++)
        {
            collection[i] = value;
        }
    }
}