aoc 2017, days 1-20

1 files changed, 71 insertions, 0 deletions

diff --git a/2017/src/day02.cpp b/2017/src/day02.cpp
new file mode 100644
index 0000000..5f965bd
--- /dev/null
+++ b/2017/src/day02.cpp
@@ -0,0 +1,71 @@
+#include <algorithm>
+#include <filesystem>
+#include <fstream>
+#include <iostream>
+#include <sstream>
+#include <string>
+#include <vector>
+
+using namespace std;
+
+namespace {
+
+vector<vector<int>>
+read_file(const filesystem::path& filename)
+{
+        ifstream            file{ filename };
+        vector<vector<int>> grid;
+
+        for ( string line; getline(file, line); ) {
+                stringstream strm{ line };
+
+                vector<int> row;
+
+                for ( int value{}; strm >> value; ) {
+                        row.emplace_back(value);
+                }
+
+                grid.emplace_back(row);
+        }
+
+        return grid;
+}
+
+void
+part1(const vector<vector<int>>& grid)
+{
+        int checksum = 0;
+        for ( const auto& row: grid ) {
+                auto [min, max] = ranges::minmax_element(row);
+                checksum += *max - *min;
+        }
+        cout << "Part1: " << checksum << '\n';
+}
+
+void
+part2(const vector<vector<int>>& grid)
+{
+        int checksum = 0;
+        for ( auto row: grid ) {
+                ranges::sort(row, ranges::greater());
+
+                for ( auto it = row.begin(); it != row.end(); ++it ) {
+                        for ( auto it2 = next(it); it2 != row.end(); ++it2 ) {
+                                if ( *it % *it2 == 0 ) {
+                                        checksum += *it / *it2;
+                                }
+                        }
+                }
+        }
+        cout << "Part2: " << checksum << '\n';
+}
+
+} // namespace
+
+int
+main()
+{
+        auto grid = read_file("data/day02.txt");
+        part1(grid);
+        part2(grid);
+}