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#include <fstream>
#include <iostream>
#include <limits>
#include <map>
#include <sstream>
#include <string>
#include <tuple>
#include <vector>
using namespace std;
using record_type = tuple<string, long, long, long>;
auto
split(const string& line, char sep = ' ')
{
vector<string> parts;
stringstream input{ line };
for ( string part; getline(input, part, sep); ) {
parts.emplace_back(part);
}
return parts;
}
auto
read_file(string_view filename)
{
fstream input{ filename };
vector<record_type> records;
for ( string line; getline(input, line); ) {
auto parts = split(line);
records.emplace_back(parts[0], stol(parts[3]), stol(parts[6]), stol(parts[13])); // NOLINT
}
return records;
}
static const size_t max_seconds = 2503;
map<string, vector<long>>
calculate_distances(const vector<record_type>& records)
{
map<string, vector<long>> distances;
for ( const auto& [name, speed, sec, sec2]: records ) {
long distance = 0;
for ( size_t second = 0; second != max_seconds; ) {
for ( size_t i = 0; second != max_seconds && i != (size_t) sec; ++i ) {
distance += speed;
++second;
distances[name].emplace_back(distance);
}
for ( long i = 0; second != max_seconds && i != sec2; ++i ) {
++second;
distances[name].emplace_back(distance);
}
}
}
return distances;
}
void
part1(const vector<record_type>& records)
{
auto distances = calculate_distances(records);
long distance = numeric_limits<long>::min();
for ( const auto& record: records ) {
auto name = get<0>(record);
auto final_distance = distances[name].back();
distance = max(distance, final_distance);
}
cout << distance << endl;
}
void
part2(const vector<record_type>& records)
{
auto distances = calculate_distances(records);
map<string, long> points;
for ( size_t second = 0; second != max_seconds; ++second ) {
auto max_distance = numeric_limits<long>::min();
for ( const auto& record: records ) {
auto name = get<0>(record);
max_distance = max(max_distance, distances[name][second]);
}
for ( const auto& record: records ) {
auto name = get<0>(record);
if ( distances[name][second] == max_distance ) {
++points[name];
}
}
}
auto max_points = numeric_limits<long>::min();
for ( const auto& [name, points]: points ) {
max_points = max(max_points, points);
}
cout << max_points << endl;
}
int
main()
{
auto records = read_file("data/day14.txt");
part1(records);
part2(records);
}
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