aoc 2015, day01

1 files changed, 54 insertions, 0 deletions

diff --git a/2015/src/day01.cpp b/2015/src/day01.cpp
new file mode 100644
index 0000000..5d6d482
--- /dev/null
+++ b/2015/src/day01.cpp
@@ -0,0 +1,54 @@
+#include <fstream>
+#include <iostream>
+#include <string>
+
+using namespace std;
+
+string
+read_file(string_view filename)
+{
+        fstream input{ filename };
+        return { istreambuf_iterator<char>{ input }, {} };
+}
+
+void
+part1(string_view puzzle)
+{
+        int floor = 0;
+        for (const auto& chr : puzzle) {
+                if (chr == '(') {
+                        ++floor;
+                }
+                else if (chr == ')') {
+                        --floor;
+                }
+        }
+        cout << floor << endl;
+}
+
+void
+part2(string_view puzzle)
+{
+        int floor = 0;
+        for (string_view::size_type pos = 0; pos != puzzle.length(); ++pos) {
+                const auto chr = puzzle[pos];
+                if (chr == '(') {
+                        ++floor;
+                }
+                else if (chr == ')') {
+                        --floor;
+                }
+                if (floor == -1) {
+                        cout << pos+1 << endl;
+                        break;
+                }
+        }
+}
+
+int
+main()
+{
+        auto puzzle = read_file("data/day01.txt");
+        part1(puzzle);
+        part2(puzzle);
+}