Files
advent-of-code/2018/puzzle-14-01.cc

49 lines
1.1 KiB
C++

//
// Created by Matthew Gretton-Dann on 01/12/2022.
//
#include <cassert>
#include <array>
#include <cstdlib>
#include <iomanip>
#include <iostream>
#include <regex>
#include <utility>
using Int = std::int64_t;
using UInt = std::uint64_t;
using Point = std::pair<Int, Int>;
auto main() -> int
{
std::string line;
if (!std::getline(std::cin, line)) {
std::cerr << "Unable to read line.\n";
return EXIT_FAILURE;
}
UInt const rounds{std::stoull(line)};
std::vector<uint8_t> scores;
scores.push_back(3);
scores.push_back(7);
UInt elf1_pos{0};
UInt elf2_pos{1};
while (scores.size() < rounds + 10) {
uint8_t const new_score{static_cast<std::uint8_t>(scores[elf1_pos] + scores[elf2_pos])};
assert(new_score < 100);
if (new_score >= 10) {
scores.push_back(new_score / 10);
}
scores.push_back(new_score % 10);
elf1_pos = (elf1_pos + 1 + scores[elf1_pos]) % scores.size();
elf2_pos = (elf2_pos + 1 + scores[elf2_pos]) % scores.size();
}
std::cout << "Score: ";
for (UInt idx{rounds}; idx < rounds + 10; ++idx) {
std::cout << static_cast<UInt>(scores[idx]);
}
std::cout << "\n";
}