day 8, part 1, advent of code 2022

1 files changed, 68 insertions, 0 deletions

diff --git a/2022/src/day08.cpp b/2022/src/day08.cpp
new file mode 100644
index 0000000..f46fdc6
--- /dev/null
+++ b/2022/src/day08.cpp
@@ -0,0 +1,68 @@
+#include <cstddef>
+#include <fstream>
+#include <iostream>
+#include <set>
+#include <string>
+#include <vector>
+using namespace std;
+
+vector<string>
+read_file(string_view filename)
+{
+        fstream        input{ filename };
+        vector<string> data;
+
+        for ( string line; getline(input, line); ) {
+                data.emplace_back(line);
+        }
+
+        return data;
+}
+
+void
+part1(const vector<string>& data)
+{
+        set<tuple<size_t, size_t>> positions;
+
+        char max_so_far = 0;
+
+        auto update = [&](size_t row, size_t col) {
+                if ( data[row][col] > max_so_far ) {
+                        positions.emplace(row, col);
+                        max_so_far = data[row][col];
+                }
+        };
+
+        for ( size_t row = 0; row != data.size(); ++row ) {
+                max_so_far = 0;
+                for ( size_t col = 0; col != data[row].size(); ++col ) {
+                        update(row, col);
+                }
+
+                max_so_far = 0;
+                for ( size_t col = data[row].size(); col-- > 0; ) {
+                        update(row, col);
+                }
+        }
+
+        for ( size_t col = 0; col != data[0].size(); ++col ) {
+                max_so_far = 0;
+                for ( size_t row = 0; row != data.size(); ++row ) {
+                        update(row, col);
+                }
+
+                max_so_far = 0;
+                for ( size_t row = data.size(); row-- > 0; ) {
+                        update(row, col);
+                }
+        }
+
+        cout << positions.size() << endl;
+}
+
+int
+main()
+{
+        const auto grid = read_file("data/day08.txt");
+        part1(grid);
+}