day 10, part 1, aoc 2022

1 files changed, 44 insertions, 0 deletions

diff --git a/2022/src/day10.cpp b/2022/src/day10.cpp
new file mode 100644
index 0000000..76c953c
--- /dev/null
+++ b/2022/src/day10.cpp
@@ -0,0 +1,44 @@
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+using namespace std;
+
+vector<int>
+read_file(string_view filename)
+{
+        fstream     input{ filename };
+        vector<int> cycles{};
+        int         reg_x = 1;
+
+        static const string add_instr = "addx ";
+
+        for ( string line; getline(input, line); ) {
+                cycles.emplace_back(reg_x);
+
+                if ( line.starts_with(add_instr) ) {
+                        cycles.emplace_back(reg_x);
+                        reg_x += stoi(line.substr(add_instr.size()));
+                }
+        }
+        cycles.emplace_back(reg_x);
+
+        return cycles;
+}
+
+void
+part1(const vector<int>& cycles)
+{
+        int sum = 0;
+        for ( size_t cycle = 19; cycle < cycles.size(); cycle += 40 ) {
+                sum += static_cast<int>(cycle + 1) * cycles[cycle];
+        }
+        cout << sum << endl;
+}
+
+int
+main()
+{
+        const auto cycles = read_file("data/day10.txt");
+        part1(cycles);
+}