1 files changed, 50 insertions, 0 deletions

diff --git a/2022/src/day04.cpp b/2022/src/day04.cpp
new file mode 100644
index 0000000..e3e4cd1
--- /dev/null
+++ b/2022/src/day04.cpp
@@ -0,0 +1,50 @@
+#include <algorithm>
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <tuple>
+#include <vector>
+using namespace std;
+
+vector<tuple<int, int, int, int>>
+read_file(string_view filename)
+{
+        fstream                           input{ filename };
+        vector<tuple<int, int, int, int>> data;
+
+        for ( string line; getline(input, line); ) {
+                int a, b, c, d;
+                (void) sscanf(line.c_str(), "%d-%d,%d-%d", &a, &b, &c, &d);
+                data.emplace_back(a, b, c, d);
+        }
+
+        return data;
+}
+
+void
+part1(const vector<tuple<int, int, int, int>>& data)
+{
+        auto sum = count_if(begin(data), end(data), [](auto& tuple) {
+                const auto [a, b, c, d] = tuple;
+                return (a <= c && b >= d) || (c <= a && d >= b);
+        });
+        cout << sum << endl;
+}
+
+void
+part2(const vector<tuple<int, int, int, int>>& data)
+{
+        auto sum = count_if(begin(data), end(data), [](auto& tuple) {
+                const auto [a, b, c, d] = tuple;
+                return max(a, c) <= min(b, d);
+        });
+        cout << sum << endl;
+}
+
+int
+main()
+{
+        const auto data = read_file("data/day04.txt");
+        part1(data);
+        part2(data);
+}