Machine Coding Question: Design Snake & Ladder

Machine Coding·Machine Coding Questions·5 min read·Sep 6, 2026

Design and implement a multiplayer Snake & Ladder game — authentication, board setup, dice-based turns, win detection, and multi-board bonus features.

Asked inSwiggyMeeshoFlipkartAmazonMicrosoft

Design and implement a Snake & Ladder game where multiple logged-in players take turns rolling a dice, climbing ladders, sliding down snakes, and racing to be the first to reach the final cell.

What the round tests

This one tests whether you can model a randomized board (snake and ladder placement) cleanly, handle turn-based multiplayer state, and keep the movement and win logic correct as you layer on dice variants and multiple simultaneous games.

Objective

The primary objective of this project is to design and implement a Snake & Ladder game on an n x n board that supports authenticated multiplayer sessions, randomized (or custom) snake and ladder placement, dice-based turns, and correct win detection when a player reaches the final cell exactly.

Functional Requirements

Three tiers of scope

Requirements are split into three tiers so you know what to prioritize under time pressure: build first, build if time allows, and discuss only.

Part 1 — Basic Requirements

Core functionality you must build and get working first.

1. User Authentication

Auth rules

Rule

Detail

Users can log in and log out of the system.

Join restriction

Only logged-in users can join a game.

2. Game Setup

Setup rules

Rule

Detail

Board

Played on an n x n board (min size 10 x 10), numbered 1 to n².

Snakes & ladders

The board has i ≤ n snakes and j ≤ n ladders, placed randomly. Snake heads sit at a higher number than their tail; ladders start lower and end higher.

Players

Supports multiple players, each starting at position 0. Minimum 2 players; maximum is half the board size (n/2).

Initialization

The board can be initialized randomly with snakes and ladders.

3. Rules

Turn-based gameplay

Rule

Detail

Dice roll

Players take turns rolling a six-sided dice (1 to 6) and move forward by the rolled number.

Landing on a snake

If the player lands on a snake's head, they move down to the tail.

Landing on a ladder

If the player lands on a ladder's start, they move up to the end.

Overshoot

If a move would exceed 100, the player stays at their original position.

Win condition

The first player to reach exactly 100 wins.

Game continuation

Rule

Detail

Minimum players

The game continues as long as at least two players are still in the game.

More than two players

With more than two players, the game continues until only one player is left.

One dice rules

Rule

Detail

Single roll

Players roll one dice per turn (values 1–6).

Rolling a 6

Grants the player an extra turn.

Optional rule

Three consecutive 6s cancel the turn and return the player to their original position.

Current Movement Logic

At present, player movement is based on the total sum of the dice values. For example, a roll of [6, 2] results in a single move of 6 + 2 = 8 steps forward.

4. Additional Assumptions

Assumptions

Assumption

Detail

Final cell

Cell 100 will never be the head of a snake.

Unique starts

No two snakes or ladders will start from the same position.

Winnable

The game is guaranteed to be winnable — reaching cell 100 (or n) is always possible.

No loops

Snake and ladder placements will not result in any infinite loops.

No chaining

A ladder or snake cannot start where another one ends.

Safe start zone

Snakes and ladders typically don't apply on the first 6 places.

Part 2 — Bonus Features

Bonus — score higher if time allows

Extensibility checks — can your design support multiple simultaneous boards, alternate dice rules, and custom setups without a rewrite.

Bonus features

Feature

What to build

Multiple Boards

Support multiple boards running several games at the same time.

Multiple Dice

Support two-dice play (combined values 2–12); see the two-dice rules below.

Customizable Board

Let players present in the game initialize the board with custom snake and ladder positions.

Game Start Rules

A player must roll a specific number (usually 6 or 1) to enter the board; until then they stay at position 0. Once on the board, they move normally.

Two dice rules

Rule

Detail

Two-dice roll

Players roll two dice per turn (each valued 1–6).

Double 6s

Rolling double 6s (6 + 6) grants an extra turn.

Single 6

Rolling a single 6 (not a double) does not grant an extra turn.

Optional rule

Three consecutive double 6s can cancel the turn and reset the player.

Part 3 — Future Enhancements

Future — discuss, don't build now

Discuss-only evolution — how the system could grow next.

AI player strategy

Level

Behavior

Basic AI

Rolls the dice and moves like a regular player — climbs ladders and slides down snakes as encountered.

Advanced AI (smart moves)

Prefers moves that land on maximum distance and avoids landing on snake heads where possible.

Custom movement strategies

Feature

Why it matters

Ordered dice use

Instead of always using the total sum, players may use dice values separately and in a chosen order — e.g., with [6, 2], use 6 first to land on a ladder and climb, then use 2; or use 2 first if it leads to a better path.

Pause / Resume / Replay

Players can pause and resume the game at any time, or replay a completed game.

Example Usage: Full Walkthrough

Here's how a sample playthrough runs end-to-end, one step at a time.

1. Log in

🟢 Welcome to Snake & Ladder Game 🐍🪜

🔐 Please log in to continue.

> Username: alice
> Password: *****
✅ Login successful. Welcome, Alice!

> Username: bob
> Password: *****
✅ Login successful. Welcome, Bob!

2. Create the game and initialize the board

🎮 Step 1: Create Game
> Creating a new Snake & Ladder game with board size 10x10...
> Game initialized with 6 snakes and 6 ladders.

🐍 Snake Positions:
 - Head at 99 → Tail at 54
 - Head at 87 → Tail at 24
 - Head at 62 → Tail at 19
 - Head at 48 → Tail at 26
 - Head at 36 → Tail at 6
 - Head at 32 → Tail at 10

🪜 Ladder Positions:
 - Start at 3 → End at 22
 - Start at 5 → End at 8
 - Start at 11 → End at 26
 - Start at 20 → End at 29
 - Start at 27 → End at 84
 - Start at 40 → End at 59

3. Add players

👥 Step 2: Add Players
> Adding player: Alice
> Adding player: Bob

✅ All players added. Ready to play!

4. Play through turns

🟢 Game Start!
-----------------------------------
🎲 Turn 1:
Alice rolls the dice... 🎲 4
Alice moves from 0 to 4

Bob rolls the dice... 🎲 6
Bob moves from 0 to 6

-----------------------------------
🎲 Turn 2:
Alice rolls the dice... 🎲 1
Alice moves from 4 to 5
🚀 Alice found a ladder! Climbs up to 8

Bob rolls the dice... 🎲 2
Bob moves from 6 to 8

-----------------------------------
🎲 Turn 3:
Alice rolls the dice... 🎲 3
Alice moves from 8 to 11
🚀 Alice found a ladder! Climbs up to 26

Bob rolls the dice... 🎲 6
Bob moves from 8 to 14

-----------------------------------
🎲 Turn 4:
Alice rolls the dice... 🎲 1
Alice moves from 26 to 27
🚀 Alice found a ladder! Climbs up to 84

Bob rolls the dice... 🎲 5
Bob moves from 14 to 19

...

5. A player reaches 100 and wins

🎉 Alice rolls a 2 and lands on 100!
🎊 Alice wins the game! 🏆

Game Over.
🔚 Bob has left the game.

Thank you for playing!

Result

Alice reaches exactly 100 via a run of ladder climbs and wins the game. Bob remains one move behind when the game ends, and the session closes cleanly once a winner is declared.

Machine Coding Question: Design Snake & Ladder

Machine Coding·Machine Coding Questions·5 min read·Sep 6, 2026

Design and implement a multiplayer Snake & Ladder game — authentication, board setup, dice-based turns, win detection, and multi-board bonus features.

Asked inSwiggyMeeshoFlipkartAmazonMicrosoft

Design and implement a Snake & Ladder game where multiple logged-in players take turns rolling a dice, climbing ladders, sliding down snakes, and racing to be the first to reach the final cell.

What the round tests

Objective

Functional Requirements

Three tiers of scope

Requirements are split into three tiers so you know what to prioritize under time pressure: build first, build if time allows, and discuss only.

Part 1 — Basic Requirements

Core functionality you must build and get working first.

1. User Authentication

Auth rules

Rule

Detail

Users can log in and log out of the system.

Join restriction

Only logged-in users can join a game.

2. Game Setup

Setup rules

Rule

Detail

Board

Played on an n x n board (min size 10 x 10), numbered 1 to n².

Snakes & ladders

The board has i ≤ n snakes and j ≤ n ladders, placed randomly. Snake heads sit at a higher number than their tail; ladders start lower and end higher.

Players

Supports multiple players, each starting at position 0. Minimum 2 players; maximum is half the board size (n/2).

Initialization

The board can be initialized randomly with snakes and ladders.

3. Rules

Turn-based gameplay

Rule

Detail

Dice roll

Players take turns rolling a six-sided dice (1 to 6) and move forward by the rolled number.

Landing on a snake

If the player lands on a snake's head, they move down to the tail.

Landing on a ladder

If the player lands on a ladder's start, they move up to the end.

Overshoot

If a move would exceed 100, the player stays at their original position.

Win condition

The first player to reach exactly 100 wins.

Game continuation

Rule

Detail

Minimum players

The game continues as long as at least two players are still in the game.

More than two players

With more than two players, the game continues until only one player is left.

One dice rules

Rule

Detail

Single roll

Players roll one dice per turn (values 1–6).

Rolling a 6

Grants the player an extra turn.

Optional rule

Three consecutive 6s cancel the turn and return the player to their original position.

Current Movement Logic

At present, player movement is based on the total sum of the dice values. For example, a roll of [6, 2] results in a single move of 6 + 2 = 8 steps forward.

4. Additional Assumptions

Assumptions

Assumption

Detail

Final cell

Cell 100 will never be the head of a snake.

Unique starts

No two snakes or ladders will start from the same position.

Winnable

The game is guaranteed to be winnable — reaching cell 100 (or n) is always possible.

No loops

Snake and ladder placements will not result in any infinite loops.

No chaining

A ladder or snake cannot start where another one ends.

Safe start zone

Snakes and ladders typically don't apply on the first 6 places.

Part 2 — Bonus Features

Bonus — score higher if time allows

Extensibility checks — can your design support multiple simultaneous boards, alternate dice rules, and custom setups without a rewrite.

Bonus features

Feature

What to build

Multiple Boards

Support multiple boards running several games at the same time.

Multiple Dice

Support two-dice play (combined values 2–12); see the two-dice rules below.

Customizable Board

Let players present in the game initialize the board with custom snake and ladder positions.

Game Start Rules

A player must roll a specific number (usually 6 or 1) to enter the board; until then they stay at position 0. Once on the board, they move normally.

Two dice rules

Rule

Detail

Two-dice roll

Players roll two dice per turn (each valued 1–6).

Double 6s

Rolling double 6s (6 + 6) grants an extra turn.

Single 6

Rolling a single 6 (not a double) does not grant an extra turn.

Optional rule

Three consecutive double 6s can cancel the turn and reset the player.

Part 3 — Future Enhancements

Future — discuss, don't build now

Discuss-only evolution — how the system could grow next.

AI player strategy

Level

Behavior

Basic AI

Rolls the dice and moves like a regular player — climbs ladders and slides down snakes as encountered.

Advanced AI (smart moves)

Prefers moves that land on maximum distance and avoids landing on snake heads where possible.

Custom movement strategies

Feature

Why it matters

Ordered dice use

Pause / Resume / Replay

Players can pause and resume the game at any time, or replay a completed game.

Example Usage: Full Walkthrough

Here's how a sample playthrough runs end-to-end, one step at a time.

1. Log in

🟢 Welcome to Snake & Ladder Game 🐍🪜

🔐 Please log in to continue.

> Username: alice
> Password: *****
✅ Login successful. Welcome, Alice!

> Username: bob
> Password: *****
✅ Login successful. Welcome, Bob!

2. Create the game and initialize the board

🎮 Step 1: Create Game
> Creating a new Snake & Ladder game with board size 10x10...
> Game initialized with 6 snakes and 6 ladders.

🐍 Snake Positions:
 - Head at 99 → Tail at 54
 - Head at 87 → Tail at 24
 - Head at 62 → Tail at 19
 - Head at 48 → Tail at 26
 - Head at 36 → Tail at 6
 - Head at 32 → Tail at 10

🪜 Ladder Positions:
 - Start at 3 → End at 22
 - Start at 5 → End at 8
 - Start at 11 → End at 26
 - Start at 20 → End at 29
 - Start at 27 → End at 84
 - Start at 40 → End at 59

3. Add players

👥 Step 2: Add Players
> Adding player: Alice
> Adding player: Bob

✅ All players added. Ready to play!

4. Play through turns

🟢 Game Start!
-----------------------------------
🎲 Turn 1:
Alice rolls the dice... 🎲 4
Alice moves from 0 to 4

Bob rolls the dice... 🎲 6
Bob moves from 0 to 6

-----------------------------------
🎲 Turn 2:
Alice rolls the dice... 🎲 1
Alice moves from 4 to 5
🚀 Alice found a ladder! Climbs up to 8

Bob rolls the dice... 🎲 2
Bob moves from 6 to 8

-----------------------------------
🎲 Turn 3:
Alice rolls the dice... 🎲 3
Alice moves from 8 to 11
🚀 Alice found a ladder! Climbs up to 26

Bob rolls the dice... 🎲 6
Bob moves from 8 to 14

-----------------------------------
🎲 Turn 4:
Alice rolls the dice... 🎲 1
Alice moves from 26 to 27
🚀 Alice found a ladder! Climbs up to 84

Bob rolls the dice... 🎲 5
Bob moves from 14 to 19

...

5. A player reaches 100 and wins

🎉 Alice rolls a 2 and lands on 100!
🎊 Alice wins the game! 🏆

Game Over.
🔚 Bob has left the game.

Thank you for playing!

Result

Alice reaches exactly 100 via a run of ladder climbs and wins the game. Bob remains one move behind when the game ends, and the session closes cleanly once a winner is declared.