puzzle-solver/tests/hidato.rs

120 lines
2.9 KiB
Rust

//! Hidato.
//!
//! https://en.wikipedia.org/wiki/Hidato
extern crate puzzle_solver;
use puzzle_solver::{Puzzle, Solution, Val, VarToken};
const WIDTH: usize = 8;
const HEIGHT: usize = 8;
const NA: i32 = -1;
type Board = [[i32; WIDTH]; HEIGHT];
fn make_hidato(board: &Board) -> (Puzzle, Vec<VarToken>) {
let mut sys = Puzzle::new();
let mut pos = Vec::new();
let mut count = 0;
for y in 0..HEIGHT {
for x in 0..WIDTH {
if board[y][x] != NA {
pos.push((WIDTH * y + x) as Val);
count += 1;
}
}
}
let vars = sys.new_vars(count, pos);
for y in 0..HEIGHT {
for x in 0..WIDTH {
if board[y][x] > 0 {
let idx = (board[y][x] - 1) as usize;
sys.set_value(vars[idx], (WIDTH * y + x) as Val);
}
}
}
sys.all_different(&vars);
let stride = WIDTH as Val;
let deltas = [
-stride - 1,
-stride,
-stride + 1,
-1,
1,
stride - 1,
stride,
stride + 1,
];
for i in 1..vars.len() {
let step = sys.new_var(&deltas);
sys.equals(vars[i], vars[i - 1] + step);
}
(sys, vars)
}
fn print_hidato(dict: &Solution, vars: &[VarToken]) {
let mut board = [[NA; WIDTH]; HEIGHT];
for (idx, &var) in vars.iter().enumerate() {
let x = (dict[var] as usize) % WIDTH;
let y = (dict[var] as usize) / WIDTH;
board[y][x] = (idx as i32) + 1;
}
for y in 0..HEIGHT {
for x in 0..WIDTH {
if board[y][x] == NA {
print!(" --");
} else {
print!(" {:2}", board[y][x]);
}
}
println!();
}
}
fn verify_hidato(dict: &Solution, vars: &[VarToken], expected: &Board) {
for (idx, &var) in vars.iter().enumerate() {
let x = (dict[var] as usize) % WIDTH;
let y = (dict[var] as usize) / WIDTH;
assert_eq!((idx as i32) + 1, expected[y][x]);
}
}
#[test]
fn hidato_wikipedia() {
let puzzle = [
[0, 33, 35, 0, 0, NA, NA, NA],
[0, 0, 24, 22, 0, NA, NA, NA],
[0, 0, 0, 21, 0, 0, NA, NA],
[0, 26, 0, 13, 40, 11, NA, NA],
[27, 0, 0, 0, 9, 0, 1, NA],
[NA, NA, 0, 0, 18, 0, 0, NA],
[NA, NA, NA, NA, 0, 7, 0, 0],
[NA, NA, NA, NA, NA, NA, 5, 0],
];
let expected = [
[32, 33, 35, 36, 37, NA, NA, NA],
[31, 34, 24, 22, 38, NA, NA, NA],
[30, 25, 23, 21, 12, 39, NA, NA],
[29, 26, 20, 13, 40, 11, NA, NA],
[27, 28, 14, 19, 9, 10, 1, NA],
[NA, NA, 15, 16, 18, 8, 2, NA],
[NA, NA, NA, NA, 17, 7, 6, 3],
[NA, NA, NA, NA, NA, NA, 5, 4],
];
let (mut sys, vars) = make_hidato(&puzzle);
let dict = sys.solve_any().expect("solution");
print_hidato(&dict, &vars);
verify_hidato(&dict, &vars, &expected);
println!("hidato_wikipedia: {} guesses", sys.num_guesses());
}