day 6

1 files changed, 32 insertions, 0 deletions

diff --git a/22.6/main.cpp b/22.6/main.cpp
new file mode 100644
index 0000000..e7eee34
--- /dev/null
+++ b/22.6/main.cpp
@@ -0,0 +1,32 @@
+#include <iostream>
+#include <algorithm>
+#include <string>
+using namespace std;
+
+int
+part1(string signal, int target)
+{
+	constexpr int amt = 'z' - 'a' + 1;
+	int last[amt];
+	int last_rep = -1;
+	fill(begin(last), end(last), -10);
+	for (int i = 0; i < signal.length(); i++) {
+		int c = signal[i] - 'a';
+		if (c >= amt) throw "bad input";
+		last_rep = max(last_rep, last[c]);
+		if (i - last_rep >= target) {
+			return i + 1;
+		}
+		last[c] = i;
+	}
+	return -1;
+}
+
+int
+main()
+{
+	for (string line; getline(cin, line); ) {
+		cout << part1(line, 4) << endl;
+		cout << part1(line, 14) << endl;
+	}
+}