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const std = @import("std");
const print = std.debug.print;
const assert = std.debug.assert;
const ArrayList = std.ArrayList;
const HashMap = std.HashMap;
const mem = std.mem;
const fin = mem.trim(u8, @embedFile("./input.txt"), &std.ascii.whitespace);
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();
fn hash(s: []const u8) u64 {
var h: u64 = 0;
for (s) |c| {
h += c;
h *= 17;
h %= 256;
}
return @bitCast(h);
}
fn part1(strings: []const []const u8) void {
var ans: u64 = 0;
for (strings) |s| {
ans += hash(s);
}
print("{d}\n", .{ans});
}
const Pair = struct {
label: []const u8,
value: u64,
};
fn part2(strings: []const []const u8) !void {
var map: [256]ArrayList(Pair) = undefined;
for (&map) |*e| {
e.* = ArrayList(Pair).init(allocator);
}
for (strings) |s| {
const action = s[mem.indexOfAny(u8, s, "-=").?];
var toks = mem.tokenizeAny(u8, s, "-=");
const label = toks.next().?;
const value = toks.next();
if (action == '=') {
const v = try std.fmt.parseInt(u64, value.?, 10);
const m = &map[hash(label)];
for (m.items) |*i| {
if (mem.eql(u8, i.label, label)) {
i.value = v;
break;
}
} else {
try map[hash(label)].append(Pair{
.value = v,
.label = label,
});
}
} else {
var m = &map[hash(label)];
for (m.items, 0..) |e, i| {
if (mem.eql(u8, e.label, label)) {
_ = m.orderedRemove(i);
break;
}
}
}
}
var ans: u64 = 0;
for (map, 1..) |m, i| {
for (m.items, 1..) |e, j| {
ans += i * j * e.value;
}
}
print("{d}\n", .{ans});
}
pub fn solve(strings: []const []const u8) !void {
part1(strings);
try part2(strings);
}
pub fn main() !void {
var splitComma = mem.splitScalar(u8, fin, ',');
var strings = ArrayList([]const u8).init(allocator);
while (splitComma.next()) |s| {
try strings.append(s);
}
try solve(strings.items);
}
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