using System;
/*
* generic_swap
* ------------
* A fully generic C# swap function implemented using generics.
*
* Parameters:
* a, b - variables passed by reference so their values can be swapped
*
* This function uses a temporary variable and assignment, which is the
* idiomatic and type‑safe way to swap objects in C#. It works for:
* - built‑in types (int, double, etc.)
* - string
* - structs/classes
* - containers
* - user‑defined types with a valid swap operation
*/
static class SwapUtils
{
public static void GenericSwap<T>(ref T a, ref T b) {
T temp = a;
a = b;
b = temp;
}
}
/*
* Print arrays of integers
*/
static class Utils
{
public static void PrintIntArray(int[] arr) {
foreach (int v in arr)
Console.Write(v + " ");
Console.WriteLine();
}
}
/*
* C# equivalent of the C++ struct Point
*/
struct Point
{
public int X;
public int Y;
public Point(int x, int y) {
X = x;
Y = y;
}
public override string ToString() => $"({X},{Y})";
}
class Program
{
static void Main()
{
Console.WriteLine("=== TEST 1: Swap integers ===");
int x = 10, y = 20;
Console.WriteLine($"Before: x={x}, y={y}");
SwapUtils.GenericSwap(ref x, ref y);
Console.WriteLine($"After: x={x}, y={y}\n");
Console.WriteLine("=== TEST 2: Swap doubles ===");
double a = 3.14, b = 2.71;
Console.WriteLine($"Before: a={a}, b={b}");
SwapUtils.GenericSwap(ref a, ref b);
Console.WriteLine($"After: a={a}, b={b}\n");
Console.WriteLine("=== TEST 3: Swap structs ===");
Point p1 = new Point(1, 2);
Point p2 = new Point(9, 8);
Console.WriteLine($"Before: p1={p1}, p2={p2}");
SwapUtils.GenericSwap(ref p1, ref p2);
Console.WriteLine($"After: p1={p1}, p2={p2}\n");
Console.WriteLine("=== TEST 4: Swap array elements ===");
int[] arr = { 1, 2, 3, 4, 5 };
Console.Write("Before: ");
Utils.PrintIntArray(arr);
SwapUtils.GenericSwap(ref arr[1], ref arr[3]);
Console.Write("After: ");
Utils.PrintIntArray(arr);
Console.WriteLine();
Console.WriteLine("=== TEST 5: Swap strings ===");
string str1 = "Hello";
string str2 = "World";
Console.WriteLine($"Before: str1=\"{str1}\", str2=\"{str2}\"");
SwapUtils.GenericSwap(ref str1, ref str2);
Console.WriteLine($"After: str1=\"{str1}\", str2=\"{str2}\"\n");
}
}
/*
run:
=== TEST 1: Swap integers ===
Before: x=10, y=20
After: x=20, y=10
=== TEST 2: Swap doubles ===
Before: a=3.14, b=2.71
After: a=2.71, b=3.14
=== TEST 3: Swap structs ===
Before: p1=(1,2), p2=(9,8)
After: p1=(9,8), p2=(1,2)
=== TEST 4: Swap array elements ===
Before: 1 2 3 4 5
After: 1 4 3 2 5
=== TEST 5: Swap strings ===
Before: str1="Hello", str2="World"
After: str1="World", str2="Hello"
*/
