aoc 2015, day 8

1 files changed, 71 insertions, 0 deletions

diff --git a/2015/src/day08.cpp b/2015/src/day08.cpp
new file mode 100644
index 0000000..9cd6e21
--- /dev/null
+++ b/2015/src/day08.cpp
@@ -0,0 +1,71 @@
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+
+using namespace std;
+
+auto
+read_file(string_view filename)
+{
+        fstream        input{ filename };
+        vector<string> lines;
+
+        for ( string line; getline(input, line); ) {
+                lines.emplace_back(line);
+        }
+
+        return lines;
+}
+
+void
+part1(const vector<string>& lines)
+{
+        auto count = [](const string& line) -> size_t {
+                size_t length = 0;
+                auto   iter   = begin(line);
+
+                while ( iter != end(line) ) {
+                        if ( *iter == '\\' ) {
+                                ++iter;
+                                if ( *iter == '\\' || *iter == '"' ) {
+                                        ++length;
+                                        ++iter;
+                                }
+                                else if ( *iter == 'x' ) {
+                                        ++length;
+                                        iter += 3;
+                                }
+                        }
+                        else {
+                                ++iter;
+                                ++length;
+                        }
+                }
+                return length - 2;
+        };
+
+        size_t sum = 0;
+        for ( const auto& line: lines ) {
+                sum += line.size() - count(line);
+        }
+        cout << sum << endl;
+}
+
+void
+part2(const vector<string>& lines)
+{
+        long sum = 0;
+        for ( const auto& line: lines ) {
+                sum += 2 + count_if(begin(line), end(line), [](auto chr) { return chr == '\\' || chr == '"'; });
+        }
+        cout << sum << endl;
+}
+
+int
+main()
+{
+        auto lines = read_file("data/day08.txt");
+        part1(lines);
+        part2(lines);
+}