aoc 2015, days 12, 13 and 14

1 files changed, 112 insertions, 0 deletions

diff --git a/2015/src/day14.cpp b/2015/src/day14.cpp
new file mode 100644
index 0000000..a877630
--- /dev/null
+++ b/2015/src/day14.cpp
@@ -0,0 +1,112 @@
+#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);
+}