hashiwokakero

package
v1.9.0 Latest Latest
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 Go to latest Published: Mar 22, 2026 License: MIT Imports: 20 Imported by: 0

README

Hashiwokakero

Connect islands with bridges to form a single connected group.

Hashiwokakero gameplay

How to Play

Islands are numbered circles on the grid. Each number indicates how many bridges must connect to that island. Bridges run horizontally or vertically between adjacent islands, may not cross, and can be single or double. The puzzle is solved when every island has exactly the required number of bridges and all islands are connected.

  1. Navigate to an island and press Enter or Space to select it.
  2. Press an arrow key toward an adjacent island to build a bridge.
  3. Press the same direction again to upgrade to a double bridge, or a third time to remove the bridge.
  4. Press Enter or Space again to deselect.

Controls

Navigation Mode
Key Action
Arrow keys / WASD / hjkl Jump to nearest island
Mouse left-click Focus a clicked island
Enter / Space Select island for bridging
Ctrl+R Reset puzzle
Ctrl+H Toggle full help
Escape Return to main menu
Bridge Mode (after selecting an island)
Key Action
Arrow keys / WASD / hjkl Build or cycle bridge in direction
Enter / Space Deselect island

Modes

Mode Grid Islands Description
Easy 7x7 7x7 8-10 Small grid, few islands
Medium 7x7 7x7 12-15 Moderate density
Hard 7x7 7x7 17-20 Dense island placement
Easy 9x9 9x9 12-16 Larger grid, spread out
Medium 9x9 9x9 20-24 Moderate density
Hard 9x9 9x9 28-32 Dense island placement
Easy 11x11 11x11 18-24 Large grid, spread out
Medium 11x11 11x11 30-36 Moderate density
Hard 11x11 11x11 42-48 Dense island placement
Easy 13x13 13x13 25-34 Largest grid, spread out
Medium 13x13 13x13 42-51 Moderate density
Hard 13x13 13x13 59-68 Dense island placement

Quick Start

puzzletea new hashi easy-7x7
puzzletea new hashi medium-9x9
puzzletea new hashi hard-13x13

Documentation

Overview

Package hashiwokakero implements the bridge-connecting puzzle game.

Index

Constants

This section is empty.

Variables

View Source 
var DefaultKeyMap = KeyMap{
	CursorKeyMap: game.DefaultCursorKeyMap,
	Select: key.NewBinding(
		key.WithKeys("enter", "space"),
		key.WithHelp("enter/space", "Select/Deselect"),
	),
}
View Source 
var Definition = puzzle.NewDefinition(puzzle.DefinitionSpec{
	Name:         "Hashiwokakero",
	Description:  "Connect the islands with bridges.",
	Aliases:      []string{"hashi", "bridges"},
	Modes:        ModeDefinitions,
	DailyModeIDs: puzzle.SelectModeIDsByIndex(ModeDefinitions, 3, 1),
})
View Source 
var Entry = gameentry.NewEntry(gameentry.EntrySpec{
	Definition: Definition,
	Help:       HelpContent,
	Import:     game.AdaptImport(ImportModel),
	Modes:      Modes,
	Print:      PDFPrintAdapter,
})
View Source 
var HelpContent string
View Source 
var ModeDefinitions = gameentry.BuildModeDefs(Modes)
View Source 
var Modes = []game.Mode{
	NewMode("Easy 7x7", "7x7 grid with 8-10 islands.", 7, 7, 8, 10),
	NewMode("Medium 7x7", "7x7 grid with 12-15 islands.", 7, 7, 12, 15),
	NewMode("Hard 7x7", "7x7 grid with 17-20 islands.", 7, 7, 17, 20),
	NewMode("Easy 9x9", "9x9 grid with 12-16 islands.", 9, 9, 12, 16),
	NewMode("Medium 9x9", "9x9 grid with 20-24 islands.", 9, 9, 20, 24),
	NewMode("Hard 9x9", "9x9 grid with 28-32 islands.", 9, 9, 28, 32),
	NewMode("Easy 11x11", "11x11 grid with 18-24 islands.", 11, 11, 18, 24),
	NewMode("Medium 11x11", "11x11 grid with 30-36 islands.", 11, 11, 30, 36),
	NewMode("Hard 11x11", "11x11 grid with 42-48 islands.", 11, 11, 42, 48),
	NewMode("Easy 13x13", "13x13 grid with 25-34 islands.", 13, 13, 25, 34),
	NewMode("Medium 13x13", "13x13 grid with 42-51 islands.", 13, 13, 42, 51),
	NewMode("Hard 13x13", "13x13 grid with 59-68 islands.", 13, 13, 59, 68),
}
View Source 
var PDFPrintAdapter = printAdapter{}

Functions

func New 

func New(mode HashiMode, puzzle Puzzle) game.Gamer

Types

type Bridge 

type Bridge struct {
	Island1, Island2 int // island IDs (Island1 < Island2)
	Count            int // 1 or 2
}

Bridge represents a connection between two islands.

type HashiMode 

type HashiMode struct {
	game.BaseMode
	Width      int
	Height     int
	MinIslands int
	MaxIslands int
}

func NewMode 

func NewMode(title, description string, width, height, minIslands, maxIslands int) HashiMode

func (HashiMode) Spawn 

func (h HashiMode) Spawn() (game.Gamer, error)

func (HashiMode) SpawnSeeded added in v1.3.0 

func (h HashiMode) SpawnSeeded(rng *rand.Rand) (game.Gamer, error)

type Island 

type Island struct {
	ID       int
	X, Y     int
	Required int // target bridge count (1-8)
}

Island represents a numbered node on the grid.

type KeyMap 

type KeyMap struct {
	game.CursorKeyMap
	Select key.Binding
}

type Model 

type Model struct {
	// contains filtered or unexported fields
}

func ImportModel 

func ImportModel(data []byte) (*Model, error)

func (Model) GetDebugInfo 

func (m Model) GetDebugInfo() string

func (Model) GetFullHelp 

func (m Model) GetFullHelp() [][]key.Binding

func (Model) GetSave 

func (m Model) GetSave() ([]byte, error)

func (Model) Init 

func (m Model) Init() tea.Cmd

func (Model) IsSolved 

func (m Model) IsSolved() bool

func (Model) Reset added in v1.3.0 

func (m Model) Reset() game.Gamer

func (Model) SetTitle 

func (m Model) SetTitle(t string) game.Gamer

func (Model) Update 

func (m Model) Update(msg tea.Msg) (game.Gamer, tea.Cmd)

func (Model) View 

func (m Model) View() string

type Puzzle 

type Puzzle struct {
	Width, Height int
	Islands       []Island
	Bridges       []Bridge
	// contains filtered or unexported fields
}

Puzzle holds the full game state.

func GeneratePuzzle 

func GeneratePuzzle(mode HashiMode) (Puzzle, error)

GeneratePuzzle creates a solvable hashiwokakero puzzle for the given mode.

func GeneratePuzzleSeeded added in v1.3.0 

func GeneratePuzzleSeeded(mode HashiMode, rng *rand.Rand) (Puzzle, error)

func (*Puzzle) BridgeCount 

func (p *Puzzle) BridgeCount(islandID int) int

BridgeCount returns the total number of bridges connected to an island.

func (*Puzzle) CellContent 

func (p *Puzzle) CellContent(x, y int) cellInfo

CellContent returns what occupies the given grid cell, using a lazily-built cache.

func (*Puzzle) FindAdjacentIsland 

func (p *Puzzle) FindAdjacentIsland(fromID, dx, dy int) *Island

FindAdjacentIsland casts a ray from the island at fromID in direction (dx,dy) and returns the first island hit, or nil. dx/dy must be (0,1),(0,-1),(1,0),(-1,0). Stops if a perpendicular bridge crosses the path.

func (*Puzzle) FindIslandAt 

func (p *Puzzle) FindIslandAt(x, y int) *Island

FindIslandAt returns the island at (x,y), or nil.

func (*Puzzle) FindIslandByID 

func (p *Puzzle) FindIslandByID(id int) *Island

FindIslandByID returns the island with the given ID, or nil.

func (*Puzzle) GetBridge 

func (p *Puzzle) GetBridge(id1, id2 int) *Bridge

GetBridge returns the bridge between two islands (by ID), or nil.

func (*Puzzle) IsConnected 

func (p *Puzzle) IsConnected() bool

IsConnected checks if all islands form a single connected component via bridges.

func (*Puzzle) IsSolved 

func (p *Puzzle) IsSolved() bool

IsSolved returns true if the puzzle is completely and correctly solved.

func (*Puzzle) SetBridge 

func (p *Puzzle) SetBridge(id1, id2, count int)

SetBridge sets or removes the bridge between two islands. count=0 removes the bridge. count must be 0, 1, or 2.

func (*Puzzle) WouldCross 

func (p *Puzzle) WouldCross(id1, id2 int) bool

WouldCross checks if adding a bridge between id1 and id2 would cross any existing bridge.

type Save 

type Save struct {
	Width     int      `json:"width"`
	Height    int      `json:"height"`
	Islands   []Island `json:"islands"`
	Bridges   []Bridge `json:"bridges"`
	ModeTitle string   `json:"mode_title,omitempty"`
}

Source Files

View all Source files

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