using System;
using System.Collections.Generic;
/*
A standard deck of 52 playing cards consists of four suits:
spades (♠), hearts (♥), diamonds (♦), and clubs (♣).
Each suit contains 13 ranks:
Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King.
Cards of spades and clubs are black, while hearts and diamonds are red.
Color is informational only — it does not affect shuffling or random selection.
*/
/*
This program performs multiple draws of 5 random cards from a 52‑card deck
WITHOUT duplicates across draws.
It uses:
- List<string> for the deck
- Fisher–Yates shuffle for efficient randomization
- Random for high‑quality randomness
Algorithm:
1. Build a full deck (52 cards)
2. For each draw:
a. Shuffle the remaining deck
b. Draw 5 cards
c. Remove them from the deck
*/
class Program
{
static List<string> BuildDeck()
{
string[] ranks = { "2","3","4","5","6","7","8","9","10","J","Q","K","A" };
string[] suits = { "Clubs", "Diamonds", "Hearts", "Spades" };
List<string> deck = new List<string>(52);
foreach (string suit in suits) {
foreach (string rank in ranks) {
deck.Add($"{rank} of {suit}");
}
}
return deck;
}
static void ShuffleDeck(List<string> deck, Random rng)
{
// Fisher–Yates shuffle
for (int i = deck.Count - 1; i > 0; i--) {
int j = rng.Next(i + 1);
string temp = deck[i];
deck[i] = deck[j];
deck[j] = temp;
}
}
static void DrawFive(List<string> deck, int drawNumber, Random rng)
{
// Shuffle the remaining deck before this draw
ShuffleDeck(deck, rng);
Console.WriteLine($"Draw #{drawNumber}:");
for (int i = 0; i < 5; i++) {
Console.WriteLine(" " + deck[i]);
}
Console.WriteLine();
// Remove drawn cards
deck.RemoveRange(0, 5);
}
static void Main()
{
// Number of draws
int draws = 3;
List<string> deck = BuildDeck();
Random rng = new Random();
// Perform multiple draws (no duplicates)
for (int i = 1; i <= draws; i++) {
if (deck.Count < 5) {
Console.WriteLine($"Not enough cards left for draw #{i}.");
break;
}
DrawFive(deck, i, rng);
}
}
}
/*
run:
Draw #1:
10 of Clubs
8 of Hearts
6 of Diamonds
10 of Diamonds
K of Diamonds
Draw #2:
9 of Hearts
K of Spades
5 of Diamonds
5 of Clubs
K of Clubs
Draw #3:
J of Hearts
A of Clubs
7 of Diamonds
3 of Hearts
J of Clubs
*/
