aoc 2015, day02

1 files changed, 57 insertions, 0 deletions

diff --git a/2015/src/day02.cpp b/2015/src/day02.cpp
new file mode 100644
index 0000000..a2d54df
--- /dev/null
+++ b/2015/src/day02.cpp
@@ -0,0 +1,57 @@
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <tuple>
+#include <vector>
+
+using namespace std;
+
+auto
+read_file(string_view filename)
+{
+        fstream                      input{ filename };
+        vector<tuple<int, int, int>> puzzle;
+        for ( string line; getline(input, line); ) {
+                int w, h, l;
+                if ( sscanf(line.c_str(), "%dx%dx%d", &w, &h, &l) == 3 ) {
+                        puzzle.emplace_back(w, h, l);
+                }
+        }
+        return puzzle;
+}
+
+void
+part1(const vector<tuple<int, int, int>>& puzzle)
+{
+        int sum = 0;
+        for ( const auto& [w, h, l]: puzzle ) {
+                auto side1 = l * w;
+                auto side2 = w * h;
+                auto side3 = h * l;
+
+                sum += 2 * side1 + 2 * side2 + 2 * side3 + min({ side1, side2, side3 });
+        }
+        cout << sum << endl;
+}
+
+void
+part2(const vector<tuple<int, int, int>>& puzzle)
+{
+        int sum = 0;
+        for ( const auto& [w, h, l]: puzzle ) {
+                auto side1 = 2 * l;
+                auto side2 = 2 * w;
+                auto side3 = 2 * h;
+
+                sum += side1 + side2 + side3 - max({ side1, side2, side3 }) + l * w * h;
+        }
+        cout << sum << endl;
+}
+
+int
+main()
+{
+        auto puzzle = read_file("data/day02.txt");
+        part1(puzzle);
+        part2(puzzle);
+}