day 13 part 1

2 files changed, 98 insertions, 0 deletions

diff --git a/22.13/main.cpp b/22.13/main.cpp
new file mode 100644
index 0000000..4ed0e84
--- /dev/null
+++ b/22.13/main.cpp
@@ -0,0 +1,68 @@
+/* broken, i don't understand c++ templates */
+
+#include <cctype>
+#include <iostream>
+#include <memory>
+#include <stdexcept>
+#include <string>
+#include <variant>
+#include <vector>
+using namespace std;
+
+struct El
+{
+	variant<unique_ptr<vector<El>>, int> v;
+
+	template<typename T>
+	El(T v)
+	{
+		this->v = v;
+	}
+
+	void
+	print()
+	{
+		if (holds_alternative<int>(v)) {
+			cout << get<int>(v);
+		} else {
+			cout << "[";
+			for (auto &e : *get<unique_ptr<vector<El>>>(v)) {
+				e.print();
+				cout << ",";
+			}
+			cout << "]";
+		}
+	}
+};
+
+El
+parse(istream &s)
+{
+	char c = s.get();
+	if (c == '[') {
+		auto v = make_unique<vector<El>>();
+		for (;;) {
+			v->push_back(parse(s));
+			do {
+				c = s.get();
+			} while (isspace(c));
+			if (c == ']') break;
+			if (c != ',') throw invalid_argument("array sep");
+		}
+		return El(move(v));
+	}
+	if (isdigit(c)) {
+		int v;
+		s.putback(c);
+		s >> v;
+		return El(v);
+	}
+	throw invalid_argument("unexpected char");
+}
+
+int
+main()
+{
+	El a = parse(cin);
+	a.print();
+}
diff --git a/22.13/main.py b/22.13/main.py
new file mode 100644
index 0000000..25b09a1
--- /dev/null
+++ b/22.13/main.py
@@ -0,0 +1,30 @@
+import json
+import sys
+
+lines = [json.loads(s) for s in sys.stdin.readlines() if s.strip()]
+
+def cmp(a, b):
+	def tolist(v):
+		return v if type(v) == list else [v]
+	i = 0
+	while True:
+		if len(a) <= i and len(b) <= i: return 0
+		if len(a) <= i: return -1
+		if len(b) <= i: return 1
+		x = a[i]
+		y = b[i]
+		if type(x) == int and type(y) == int:
+			if x < y: return -1
+			if x > y: return 1
+		else:
+			r = cmp(tolist(x), tolist(y))
+			if r != 0: return r
+		i += 1
+
+partOne = 0
+for i in range(0, len(lines), 2):
+	a = lines[i]
+	b = lines[i+1]
+	if cmp(a,b) != 1:
+		partOne += i//2+1
+print(partOne)