151 lines
2.7 KiB
C++
151 lines
2.7 KiB
C++
#include <BAN/Array.h>
|
|
#include <BAN/LinkedList.h>
|
|
#include <BAN/String.h>
|
|
#include <BAN/StringView.h>
|
|
#include <BAN/Vector.h>
|
|
|
|
#include <ctype.h>
|
|
#include <inttypes.h>
|
|
#include <stdio.h>
|
|
|
|
using i8 = int8_t;
|
|
using i16 = int16_t;
|
|
using i32 = int32_t;
|
|
using i64 = int64_t;
|
|
|
|
using u8 = uint8_t;
|
|
using u16 = uint16_t;
|
|
using u32 = uint32_t;
|
|
using u64 = uint64_t;
|
|
|
|
i64 parse_i64(BAN::StringView string)
|
|
{
|
|
i64 result = 0;
|
|
for (char c : string)
|
|
result = (result * 10) + (c - '0');
|
|
return result;
|
|
}
|
|
|
|
BAN::Vector<BAN::StringView> parse_instructions(FILE* fp)
|
|
{
|
|
static BAN::String line;
|
|
|
|
char buffer[128];
|
|
while (fgets(buffer, sizeof(buffer), fp))
|
|
{
|
|
BAN::StringView buffer_sv(buffer);
|
|
MUST(line.append(buffer_sv));
|
|
if (buffer_sv.back() == '\n')
|
|
{
|
|
line.pop_back();
|
|
break;
|
|
}
|
|
}
|
|
|
|
return MUST(line.sv().split(','));
|
|
}
|
|
|
|
i64 calculate_hash(BAN::StringView string)
|
|
{
|
|
i64 result = 0;
|
|
for (char c : string)
|
|
result = ((result + c) * 17) % 256;
|
|
return result;
|
|
}
|
|
|
|
i64 puzzle1(FILE* fp)
|
|
{
|
|
auto instructions = parse_instructions(fp);
|
|
|
|
i64 result = 0;
|
|
for (auto insn : instructions)
|
|
result += calculate_hash(insn);
|
|
return result;
|
|
}
|
|
|
|
i64 puzzle2(FILE* fp)
|
|
{
|
|
struct Entry
|
|
{
|
|
BAN::String label;
|
|
i64 focal_length;
|
|
};
|
|
using Box = BAN::LinkedList<Entry>;
|
|
|
|
auto instructions = parse_instructions(fp);
|
|
|
|
BAN::Array<Box, 256> boxes;
|
|
|
|
for (auto insn : instructions)
|
|
{
|
|
if (insn.back() == '-')
|
|
{
|
|
auto label = insn.substring(0, insn.size() - 1);
|
|
i64 hash = calculate_hash(label);
|
|
|
|
for (auto it = boxes[hash].begin(); it != boxes[hash].end(); it++)
|
|
{
|
|
if (it->label == label)
|
|
{
|
|
boxes[hash].remove(it);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
auto temp = MUST(insn.split('='));
|
|
|
|
auto label = temp[0];
|
|
auto focal_length = parse_i64(temp[1]);
|
|
i64 hash = calculate_hash(label);
|
|
|
|
bool found = false;
|
|
for (auto it = boxes[hash].begin(); it != boxes[hash].end(); it++)
|
|
{
|
|
if (it->label == label)
|
|
{
|
|
it->focal_length = focal_length;
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!found)
|
|
MUST(boxes[hash].emplace_back(label, focal_length));
|
|
}
|
|
}
|
|
|
|
i64 result = 0;
|
|
for (size_t i = 0; i < boxes.size(); i++)
|
|
{
|
|
size_t slot = 0;
|
|
for (auto it = boxes[i].begin(); it != boxes[i].end(); it++, slot++)
|
|
result += (i + 1) * (slot + 1) * it->focal_length;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
int main(int argc, char** argv)
|
|
{
|
|
const char* file_path = "/usr/share/aoc2023/day15_input.txt";
|
|
|
|
if (argc >= 2)
|
|
file_path = argv[1];
|
|
|
|
FILE* fp = fopen(file_path, "r");
|
|
if (fp == nullptr)
|
|
{
|
|
perror("fopen");
|
|
return 1;
|
|
}
|
|
|
|
printf("puzzle1: %" PRId64 "\n", puzzle1(fp));
|
|
|
|
fseek(fp, 0, SEEK_SET);
|
|
|
|
printf("puzzle2: %" PRId64 "\n", puzzle2(fp));
|
|
|
|
fclose(fp);
|
|
}
|