ap29600

x = sum(load("in.txt")(:) == [0:8])';

A = diag(ones(1, 8), 1);
A(9, 1) = 1;
A(7, 1) = 1;

format rat

sum(A^80*x)
sum(A^256*x)

ap29600

package aoc12

import "core:fmt"
import "core:slice"
import "core:strings"

when ODIN_DEBUG {
  input :: `start-A
start-b
A-c

ap29600

use std::ops::{Index, IndexMut};
use itertools::Itertools;

struct Bitmap {
    rows: usize,
    cols: usize,
    backing: Vec<bool>,
    boundary: bool,
}

ap29600

use itertools::Itertools;
use std::collections::HashSet;

const N6:  [(i64, i64, i64); 6] = [
    ( 1, 0, 0), (0,  1, 0), (0, 0,  1),
    (-1, 0, 0), (0, -1, 0), (0, 0, -1)
];
const N14: [(i64, i64, i64); 18]= [
    ( 1,  0,  0), (0,  1,  0), ( 0,  0,  1),
    (-1,  0,  0), (0, -1,  0), ( 0,  0, -1),

ap29600

package main

import "core:os"
import "core:fmt"
import "core:slice"
import "core:mem"
import "core:strings"
import "core:strconv"

mix :: proc (numbers: []int, mix: int) -> (result: int) {

ap29600

package main

import "core:fmt"
import "core:math"
import "core:mem"
import "core:os"
import "core:slice"
import "core:unicode"
import "core:strconv"
import "core:strings"

ap29600

package main

import "core:os"
import "core:strings"
import "core:fmt"
import "core:slice"
import "core:strconv"
import "core:time"

State :: enum u8 {

ap29600

; syntax M68k
Font_height equ 10
Font_width  equ 8
font:
	dcb.b Font_height*(32-0),$55;
	; spc
	dc.b %00000000
	dc.b %00000000
	dc.b %00000000
	dc.b %00000000

ap29600

#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <stdbool.h>
#include <stdlib.h>

#define ENSURE(p) ({__typeof(p) _p = p; assert(_p); _p; })

typedef struct {
	size_t dot;

ap29600

n ← 6
k ← 4

d ← ↕n
poly ← (0.5×d+1)≍¨(-0.5×d-1)
limits ← ⌈{a‿b‿c: (2×a)÷˜-b-√(טb)-4×a×c}¨ poly ∾⌜ -10⋆k-1‿0
values ← poly {+´𝕨×(ט𝕩)‿𝕩}¨ {a‿b:<a+↕b-a}˘limits # the numbers to be tested
perm ← (n-1) ∾˘˜ (≍↕0){∾˝(0∾˘1+𝕩)⊸⊏˘⍒˘=⌜˜↕𝕨}´-⟜↕n-1 # distinct cycles of number class

{