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
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
const std = @import("std");
const aoc = @import("aoc");
const hasher = std.hash.CityHash32;
const IngredientInfo = struct {
count: u32,
};
const Pair = struct { ingredient: []const u8, allergen: []const u8 };
fn freeListmap(listmap: *std.AutoHashMap(u32, std.ArrayList(u32))) void {
var mapit = listmap.iterator();
while (mapit.next()) |kv| {
kv.value_ptr.deinit();
}
listmap.deinit();
}
fn getAllergen(allergens: *std.AutoHashMap(u32, std.ArrayList(u32)), ingredient: u32) ?u32 {
var allergenit = allergens.iterator();
while (allergenit.next()) |alg| {
if (alg.value_ptr.items.len == 1 and alg.value_ptr.items[0] == ingredient)
return alg.key_ptr.*;
}
return null;
}
fn updateAllergens(allocator: std.mem.Allocator, allergens: *std.AutoHashMap(u32, std.ArrayList(u32)), allergen: u32) !void {
var next = std.ArrayList(u32).init(allocator);
defer next.deinit();
try next.append(allergen);
while (next.items.len > 0) {
const key = next.items[0];
var ingredient = allergens.getEntry(key).?.value_ptr.items[0];
var mapit = allergens.iterator();
while (mapit.next()) |alg| {
if (alg.key_ptr.* == key) continue;
const ind = std.mem.indexOfScalar(u32, alg.value_ptr.items, ingredient);
if (ind != null) {
_ = alg.value_ptr.swapRemove(ind.?);
if (alg.value_ptr.items.len == 1) {
try next.append(alg.key_ptr.*);
}
}
}
_ = next.swapRemove(0);
}
}
fn parseAllergens(allocator: std.mem.Allocator, allergens: *std.AutoHashMap(u32, std.ArrayList(u32)), unhash: *std.AutoHashMap(u32, []const u8), ingredient_counts: *std.AutoHashMap(u32, u32), input: []const u8) !void {
var ingredients = std.ArrayList(u32).init(allocator);
defer ingredients.deinit();
var lineit = std.mem.tokenize(u8, input, "\n");
while (lineit.next()) |line| {
var allergen = false;
try ingredients.resize(0);
var spaceit = std.mem.tokenize(u8, line, " ");
while (spaceit.next()) |word| {
if (std.mem.eql(u8, word, "(contains")) {
allergen = true;
continue;
}
if (allergen) {
const allergen_name = if (word[word.len - 1] == ')' or word[word.len - 1] == ',') word[0 .. word.len - 1] else word;
const allergen_hash = hasher.hash(allergen_name);
try unhash.put(allergen_hash, allergen_name);
var algentry = allergens.getEntry(allergen_hash);
if (algentry) |algent| {
var i: u32 = 0;
while (i < algent.value_ptr.items.len) {
if (std.mem.indexOfScalar(u32, ingredients.items, algent.value_ptr.items[i]) == null) {
_ = algent.value_ptr.swapRemove(i);
} else {
i += 1;
}
}
if (algent.value_ptr.items.len == 1) {
try updateAllergens(allocator, allergens, algent.key_ptr.*);
}
} else {
var copy = std.ArrayList(u32).init(allocator);
errdefer copy.deinit();
for (ingredients.items) |ing| {
if (getAllergen(allergens, ing) == null) {
try copy.append(ing);
}
}
try allergens.put(allergen_hash, copy);
}
} else {
const ingredient_hash = hasher.hash(word);
try unhash.put(ingredient_hash, word);
try ingredients.append(ingredient_hash);
const entry = ingredient_counts.getEntry(ingredient_hash);
if (entry == null) {
try ingredient_counts.put(ingredient_hash, 1);
} else {
entry.?.value_ptr.* += 1;
}
}
}
}
}
fn ascendingAllergen(ctx: void, p1: Pair, p2: Pair) bool {
_ = ctx;
var i: u32 = 0;
while (i < std.math.min(p1.allergen.len, p2.allergen.len) and p1.allergen[i] == p2.allergen[i]) : (i += 1) {}
return p1.allergen[i] < p2.allergen[i];
}
fn part1(allocator: std.mem.Allocator, input: []u8, args: [][]u8) !?[]u8 {
_ = args;
var allergens = std.AutoHashMap(u32, std.ArrayList(u32)).init(allocator);
defer freeListmap(&allergens);
var ingredient_counts = std.AutoHashMap(u32, u32).init(allocator);
defer ingredient_counts.deinit();
var unhash = std.AutoHashMap(u32, []const u8).init(allocator);
defer unhash.deinit();
try parseAllergens(allocator, &allergens, &unhash, &ingredient_counts, input);
var answer: u32 = 0;
var algit = allergens.iterator();
while (algit.next()) |alg| {
aoc.debugfmt("{} - ", .{alg.key_ptr.*});
for (alg.value_ptr.items) |v| {
aoc.debugfmt("{} ", .{v});
}
aoc.debugfmt("\n", .{});
}
var mapit = ingredient_counts.iterator();
while (mapit.next()) |kv| {
if (getAllergen(&allergens, kv.key_ptr.*) == null) answer += kv.value_ptr.*;
}
return try std.fmt.allocPrint(allocator, "{}", .{answer});
}
fn part2(allocator: std.mem.Allocator, input: []u8, args: [][]u8) !?[]u8 {
_ = args;
var allergens = std.AutoHashMap(u32, std.ArrayList(u32)).init(allocator);
defer freeListmap(&allergens);
var ingredient_counts = std.AutoHashMap(u32, u32).init(allocator);
defer ingredient_counts.deinit();
var unhash = std.AutoHashMap(u32, []const u8).init(allocator);
defer unhash.deinit();
try parseAllergens(allocator, &allergens, &unhash, &ingredient_counts, input);
var pairs = std.ArrayList(Pair).init(allocator);
defer pairs.deinit();
var mapit = ingredient_counts.iterator();
while (mapit.next()) |kv| {
const alg = getAllergen(&allergens, kv.key_ptr.*);
if (alg != null) {
try pairs.append(Pair{ .ingredient = unhash.get(kv.key_ptr.*).?, .allergen = unhash.get(alg.?).? });
}
}
std.sort.sort(Pair, pairs.items, {}, ascendingAllergen);
var parts = std.ArrayList([]const u8).init(allocator);
defer parts.deinit();
for (pairs.items) |p, i| {
if (i > 0) try parts.append(",");
try parts.append(p.ingredient);
}
return try std.mem.join(allocator, "", parts.items);
}
const sol2 = "fqhpsl,zxncg,clzpsl,zbbnj,jkgbvlxh,dzqc,ppj,glzb";
pub const main = aoc.main(part1, part2, .{ "2584", sol2 });
|
