From 9b4d4c8d3fa747743f3d8aca251e55639f387266 Mon Sep 17 00:00:00 2001
From: Faiyaz Khira <faiyazkhira27@gmail.com>
Date: Thu, 31 Jul 2025 23:36:53 +0530
Subject: [PATCH] Snake and Ladder Solution

---
 src/Board.java  |  42 ++++++++++++++++++
 src/Dice.java   |  19 ++++++++
 src/Game.java   | 113 ++++++++++++++++++++++++++++++++++++++++++++++++
 src/Ladder.java |  17 ++++++++
 src/Player.java |  21 +++++++++
 src/Snake.java  |  17 ++++++++
 6 files changed, 229 insertions(+)
 create mode 100644 src/Board.java
 create mode 100644 src/Dice.java
 create mode 100644 src/Game.java
 create mode 100644 src/Ladder.java
 create mode 100644 src/Player.java
 create mode 100644 src/Snake.java

diff --git a/src/Board.java b/src/Board.java
new file mode 100644
index 00000000..cfd8d513
--- /dev/null
+++ b/src/Board.java
@@ -0,0 +1,42 @@
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class Board {
+    private final Map<Integer, Integer> snakes = new HashMap<>();
+    private final Map<Integer, Integer> ladders = new HashMap<>();
+    private final int boardSize;
+
+    public Board(List<Snake> snakeList, List<Ladder> ladderList, int boardSize){
+        this.boardSize = boardSize;
+        for(Snake s : snakeList){
+            snakes.put(s.getHead(), s.getTail());
+        }
+        for(Ladder l : ladderList){
+            ladders.put(l.getStart(), l.getEnd());
+        }
+    }
+
+    public int getBoardSize() {
+        return boardSize;
+    }
+
+    public int getNextPosition(int currentPosition) {
+        int newPos = currentPosition;
+
+        //handle snake and ladder logic
+        boolean moved;
+        do {
+            moved = false;
+            if(ladders.containsKey(newPos)){
+                newPos = ladders.get(newPos);
+                moved = true;
+            } else if(snakes.containsKey(newPos)){
+                newPos = snakes.get(newPos);
+                moved = true;
+            }
+        } while (moved);
+
+        return newPos;
+    }
+}
diff --git a/src/Dice.java b/src/Dice.java
new file mode 100644
index 00000000..298d4e4f
--- /dev/null
+++ b/src/Dice.java
@@ -0,0 +1,19 @@
+import java.util.Random;
+
+public class Dice {
+    private final Random random = new Random();
+    private final int diceCount;
+
+    public Dice(int diceCount) {
+        this.diceCount = diceCount;
+    }
+
+
+    public int rollDice(){
+        int total = 0;
+        for(int i=0; i<diceCount; i++){
+            total += random.nextInt(6)+1;
+        }
+        return total;
+    }
+}
\ No newline at end of file
diff --git a/src/Game.java b/src/Game.java
new file mode 100644
index 00000000..9e94da33
--- /dev/null
+++ b/src/Game.java
@@ -0,0 +1,113 @@
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Scanner;
+
+public class Game {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+
+        System.out.println("Enter the dice count:");
+        int diceCount = Integer.parseInt(scanner.nextLine().trim());
+
+        if(diceCount < 1 || diceCount > 3){
+            System.out.println("Invalid dice count. Must be between 1 and 3.");
+            return;
+        }
+
+        Dice dice = new Dice(diceCount);
+
+
+        // Read Board
+        System.out.println("Enter board dimension N (you will get an NxN board):");
+        int dimension = Integer.parseInt(scanner.nextLine().trim());
+        int boardSize = dimension * dimension;
+
+        if(dimension < 3 || dimension > 15){
+            System.out.println("Invalid dimension. Must be between 3 and 15.");
+            return;
+        }
+        System.out.println("Your board size is: " +  boardSize);
+
+
+        // Read Snakes
+        System.out.println("Enter the number of snakes:");
+        int snakeCount = Integer.parseInt(scanner.nextLine().trim());
+        List<Snake> snakeList = new ArrayList<>();
+        for(int i=0; i<snakeCount; i++){
+            System.out.println("Enter the head and tail in the format (eg. H T) for snake " + (i+1));
+            String parts[] = scanner.nextLine().trim().split(" ");
+            int head = Integer.parseInt(parts[0]);
+            int tail = Integer.parseInt(parts[1]);
+
+            if(head <= tail || head > boardSize || tail >= boardSize || head == boardSize){
+                System.out.println("Invalid snake: head must be > tail and within board size");
+                return;
+            }
+
+            snakeList.add(new Snake(head, tail));
+        }
+
+        // Read ladders
+        System.out.println("Enter the number of ladders:");
+        int ladderCount = Integer.parseInt(scanner.nextLine().trim());
+        List<Ladder> ladderList = new ArrayList<>();
+        for(int i=0; i<ladderCount; i++){
+            System.out.println("Enter the start and end in the format (eg. S E) for snake " + (i+1));
+            String[] parts = scanner.nextLine().trim().split(" ");
+            int start = Integer.parseInt(parts[0]);
+            int end = Integer.parseInt(parts[1]);
+
+            if (start >= end || start <= 0 || end > boardSize) {
+                System.out.println("Invalid ladder: start must be < end and within board size");
+                return;
+            }
+
+            ladderList.add(new Ladder(start, end));
+        }
+
+        // Read players
+        System.out.println("Enter the number of players:");
+        int playerCount = Integer.parseInt(scanner.nextLine().trim());
+        List<Player> playerList = new ArrayList<>();
+        for(int i=0; i<playerCount; i++){
+            System.out.println("Enter the name for player " + (i+1));
+            String name = scanner.nextLine().trim();
+            playerList.add(new Player(name));
+        }
+
+        // Initialize board
+        Board board = new Board(snakeList, ladderList, boardSize);
+
+        // Play game
+        boolean gameWon = false;
+        int currentPlayerIndex = 0;
+
+        while(!gameWon){
+            Player currentPlayer = playerList.get(currentPlayerIndex);
+
+            int currentPosition = currentPlayer.getPosition();
+            int diceRoll = dice.rollDice();
+            int nextPosition = currentPosition + diceRoll;
+
+            if(nextPosition > board.getBoardSize()){
+                nextPosition = currentPosition;
+            } else {
+                nextPosition = board.getNextPosition(nextPosition);
+            }
+
+            currentPlayer.setPosition(nextPosition);
+
+            System.out.printf("%s rolled %d and moved from %d to %d%n",
+                    currentPlayer.getName(), diceRoll, currentPosition, nextPosition);
+
+            if(nextPosition == 100){
+                System.out.println(currentPlayer.getName() + " wins the game");
+                gameWon = true;
+                break;
+            }
+
+            currentPlayerIndex = (currentPlayerIndex + 1) % playerList.size();
+        }
+        scanner.close();
+    }
+}
diff --git a/src/Ladder.java b/src/Ladder.java
new file mode 100644
index 00000000..e7328685
--- /dev/null
+++ b/src/Ladder.java
@@ -0,0 +1,17 @@
+public class Ladder {
+    private final int start;
+    private final int end;
+
+    public Ladder(int start, int end) {
+        this.start = start;
+        this.end = end;
+    }
+
+    public int getStart() {
+        return start;
+    }
+
+    public int getEnd() {
+        return end;
+    }
+}
diff --git a/src/Player.java b/src/Player.java
new file mode 100644
index 00000000..eba13fc5
--- /dev/null
+++ b/src/Player.java
@@ -0,0 +1,21 @@
+public class Player {
+    private final String name;
+    private int position;
+
+    public Player(String name) {
+        this.name = name;
+        this.position = 0;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getPosition() {
+        return position;
+    }
+
+    public void setPosition(int position) {
+        this.position = position;
+    }
+}
diff --git a/src/Snake.java b/src/Snake.java
new file mode 100644
index 00000000..54f6f243
--- /dev/null
+++ b/src/Snake.java
@@ -0,0 +1,17 @@
+public class Snake {
+    private final int head;
+    private final int tail;
+
+    public Snake(int head, int tail) {
+        this.head = head;
+        this.tail = tail;
+    }
+
+    public int getHead() {
+        return head;
+    }
+
+    public int getTail() {
+        return tail;
+    }
+}