39 lines
1.1 KiB
Zig
39 lines
1.1 KiB
Zig
|
const std = @import("std");
|
||
|
|
|
||
|
|
const input = @embedFile("input");
|
||
|
|
|
||
|
|
var result: [6 * 40]u8 = undefined;
|
||
|
|
|
||
|
|
pub fn main() anyerror!void {
|
||
|
|
solve(input);
|
||
|
|
var y: usize = 0;
|
||
|
|
while (y < 6) : (y += 1) {
|
||
|
|
std.debug.print("{s}\n", .{result[y * 40 .. (y + 1) * 40]});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
fn solve(puzzle: []const u8) void {
|
||
|
|
var it = std.mem.tokenize(u8, puzzle, "\n");
|
||
|
|
var cycle: usize = 0;
|
||
|
|
var x: i64 = 1;
|
||
|
|
var line: []const u8 = undefined;
|
||
|
|
var prev: ?i64 = null;
|
||
|
|
// process input
|
||
|
|
while (cycle < 40 * 6) : (cycle += 1) {
|
||
|
|
const pos = @mod(cycle, 40);
|
||
|
|
const draw = pos == x - 1 or pos == x or pos == x + 1;
|
||
|
|
result[cycle] = if (draw) '#' else '.';
|
||
|
|
if (prev) |p| { // cpu is busy adding
|
||
|
|
x += p;
|
||
|
|
prev = null;
|
||
|
|
} else { // read another instruction
|
||
|
|
line = it.next() orelse break;
|
||
|
|
if (line[0] == 'a') {
|
||
|
|
var elts = std.mem.split(u8, line, " ");
|
||
|
|
_ = elts.next() orelse unreachable;
|
||
|
|
prev = std.fmt.parseInt(i64, elts.next() orelse unreachable, 10) catch unreachable;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|