1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
const std = @import("std");
const print = std.debug.print;
const assert = std.debug.assert;
const ArrayList = std.ArrayList;
const mem = std.mem;
const fin = mem.trim(u8, @embedFile("./input.txt"), &std.ascii.whitespace);
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();
const Color = enum {
red,
green,
blue,
};
const Ball = struct {
color: Color,
num: u64,
};
const Set = struct {
red: u64,
green: u64,
blue: u64,
};
const Game = struct {
var curGameID: u64 = 1;
id: u64,
sets: ArrayList(Set),
fn init(self: *@This()) !void {
self.id = curGameID;
self.sets = ArrayList(Set).init(allocator);
curGameID += 1;
}
fn deinit(self: *@This()) void {
self.sets.deinit();
}
};
pub fn parseBall(text: []const u8) Ball {
const trimmed = mem.trim(u8, text, &std.ascii.whitespace);
var splitBalls = mem.splitScalar(u8, trimmed, ' ');
const nballs = std.fmt.parseInt(u64, splitBalls.next().?, 10) catch unreachable;
var color: Color = undefined;
color = blk: {
const s = splitBalls.next().?;
if (mem.eql(u8, s, "red")) {
break :blk .red;
}
if (mem.eql(u8, s, "green")) {
break :blk .green;
}
if (mem.eql(u8, s, "blue")) {
break :blk .blue;
}
unreachable;
};
return Ball{
.color = color,
.num = nballs,
};
}
pub fn parseSet(text: []const u8) Set {
const trimmed = mem.trim(u8, text, &std.ascii.whitespace);
var splitBalls = mem.splitScalar(u8, trimmed, ',');
var r: u64 = 0;
var g: u64 = 0;
var b: u64 = 0;
while (splitBalls.next()) |ball| {
const parsed_ball = parseBall(ball);
switch (parsed_ball.color) {
.red => r += parsed_ball.num,
.green => g += parsed_ball.num,
.blue => b += parsed_ball.num,
}
}
return Set{
.red = r,
.green = g,
.blue = b,
};
}
pub fn parseGame(text: []const u8) !Game {
const trimmed = mem.trim(u8, text, &std.ascii.whitespace);
var splitSets = mem.splitScalar(u8, trimmed, ';');
var game: Game = undefined;
try game.init();
while (splitSets.next()) |set| {
try game.sets.append(parseSet(set));
}
return game;
}
pub fn part1(input: ArrayList(Game)) void {
var ans: u64 = 0;
outer: for (input.items) |game| {
for (game.sets.items) |set| {
if (set.red > 12 or set.green > 13 or set.blue > 14) {
continue :outer;
}
}
ans += game.id;
}
print("{d}\n", .{ans});
}
pub fn part2(input: ArrayList(Game)) void {
var ans: u64 = 0;
for (input.items) |game| {
var max = Set{
.red = 0,
.blue = 0,
.green = 0,
};
for (game.sets.items) |set| {
max.red = @max(max.red, set.red);
max.green = @max(max.green, set.green);
max.blue = @max(max.blue, set.blue);
}
ans += max.red * max.green * max.blue;
}
print("{d}\n", .{ans});
}
pub fn main() !void {
var splitLines = mem.splitScalar(u8, fin, '\n');
var games = ArrayList(Game).init(allocator);
defer games.deinit();
while (splitLines.next()) |line| {
var splitGame = mem.splitScalar(u8, line, ':');
_ = splitGame.next();
const game = try parseGame(splitGame.next().?);
try games.append(game);
}
part1(games);
part2(games);
}
|
