Ilia Denisov
15c7959d96
A Go library that returns every legal play ranked by score and scores or validates plays, using the Appel-Jacobson DAWG algorithm over github.com/iliadenisov/dafsa v1.1.0. - DAWG move generation (across / down / both), full tournament scoring with a per-tile breakdown; public Solver: GenerateMoves (ranked), ScorePlay, ValidatePlay. - Rulesets: English Scrabble, Russian Scrabble, Эрудит (parameterizable Ruleset). - cmd/builddict (build the DAWG from the dictionaries submodule), cmd/stress (self-play benchmark), selfplay engine; brute-force test oracle. - A GADDAG was implemented, benchmarked and removed (the DAWG was smaller and faster for a scoring solver); see RESULTS.md and ALGORITHM.md.
106 lines
3.0 KiB
Go
106 lines
3.0 KiB
Go
// Package board holds the compact game board: a row-major grid of cell bytes encoded
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// per internal/encoding (0 = empty, letter+1, with 0x80 marking a blank). It is
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// otherwise alphabet-agnostic.
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package board
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import (
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"fmt"
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"unicode"
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"github.com/iliadenisov/alphabet"
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"scrabble-solver/internal/encoding"
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)
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// Board is a row-major grid of encoded cells.
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type Board struct {
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rows, cols int
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cells []byte
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}
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// New returns an empty rows×cols board.
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func New(rows, cols int) *Board {
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return &Board{rows: rows, cols: cols, cells: make([]byte, rows*cols)}
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}
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// Rows returns the number of rows.
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func (b *Board) Rows() int { return b.rows }
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// Cols returns the number of columns.
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func (b *Board) Cols() int { return b.cols }
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// At returns the encoded cell at (r, c).
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func (b *Board) At(r, c int) byte { return b.cells[r*b.cols+c] }
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// Set stores the encoded cell v at (r, c).
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func (b *Board) Set(r, c int, v byte) { b.cells[r*b.cols+c] = v }
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// InBounds reports whether (r, c) is on the board.
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func (b *Board) InBounds(r, c int) bool {
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return r >= 0 && r < b.rows && c >= 0 && c < b.cols
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}
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// Empty reports whether (r, c) is an empty square.
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func (b *Board) Empty(r, c int) bool { return encoding.IsEmpty(b.cells[r*b.cols+c]) }
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// Filled reports whether (r, c) is on the board and occupied.
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func (b *Board) Filled(r, c int) bool {
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return b.InBounds(r, c) && !encoding.IsEmpty(b.cells[r*b.cols+c])
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}
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// IsEmpty reports whether the whole board is empty (used for the first move).
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func (b *Board) IsEmpty() bool {
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for _, c := range b.cells {
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if !encoding.IsEmpty(c) {
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return false
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}
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}
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return true
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}
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// Clone returns a deep copy of the board.
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func (b *Board) Clone() *Board {
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cp := &Board{rows: b.rows, cols: b.cols, cells: make([]byte, len(b.cells))}
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copy(cp.cells, b.cells)
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return cp
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}
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// Transpose returns a new board with rows and columns swapped, turning vertical lines
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// into horizontal ones. Down-play generation runs on the transpose.
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func (b *Board) Transpose() *Board {
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t := &Board{rows: b.cols, cols: b.rows, cells: make([]byte, len(b.cells))}
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for r := range b.rows {
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for c := range b.cols {
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t.cells[c*t.cols+r] = b.cells[r*b.cols+c]
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}
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}
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return t
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}
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// Parse builds a board from text rows: '.' (or space) is an empty square, a lowercase
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// letter is a normal tile, and an uppercase letter is a blank standing for that letter.
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// Letters are resolved through idx.
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func Parse(rows []string, idx alphabet.Indexer) (*Board, error) {
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if len(rows) == 0 {
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return nil, fmt.Errorf("board: no rows")
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}
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cols := len([]rune(rows[0]))
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b := New(len(rows), cols)
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for r, line := range rows {
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runes := []rune(line)
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for c := 0; c < cols && c < len(runes); c++ {
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ch := runes[c]
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if ch == '.' || ch == ' ' {
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continue
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}
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blank := unicode.IsUpper(ch)
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li, err := idx.Index(string(unicode.ToLower(ch)))
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if err != nil {
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return nil, fmt.Errorf("board: row %d col %d %q: %w", r, c, string(ch), err)
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}
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b.Set(r, c, encoding.Cell(li, blank))
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}
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}
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return b, nil
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}
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