day 20 part 1

1 files changed, 47 insertions, 0 deletions

diff --git a/22.20/main.cpp b/22.20/main.cpp
new file mode 100644
index 0000000..753cdf5
--- /dev/null
+++ b/22.20/main.cpp
@@ -0,0 +1,47 @@
+/* The reason I gave up on this:
+ * I thought I'd need to somehow track the first "node", so I wanted to
+ * experiment on a more naive implementation. I don't.
+ * Also, the dumb algorithm is still by far fast enough. So, Python it is. */
+#include <cstdio>
+#include <vector>
+using namespace std;
+
+struct CNode
+{
+	size_t id;
+	CNode *prev = NULL, *next = NULL;
+};
+
+struct Circular
+{
+	vector<CNode> nodes;
+	Circular(size_t size) {
+		for (size_t i = 0; i < size; i++) {
+			nodes.push_back(CNode{i});
+		}
+
+		// pointers to stuff in a vector? how risque!
+		for (size_t i = 0; i < size - 1; i++) {
+			nodes[i].next = &nodes[i+1];
+			nodes[i+1].prev = &nodes[i];
+		}
+		CNode *f = &nodes.front();
+		CNode *b = &nodes.back();
+		f->prev = b;
+		b->next = f;
+	}
+
+	void print() {
+	}
+};
+
+int
+main()
+{
+	int n;
+	vector<int> input;
+	while (scanf("%d ", &n) == 1) {
+		input.push_back(n);
+	}
+	Circular c(input.size());
+}