1 files changed, 61 insertions, 0 deletions
diff --git a/2024/2B.cpp b/2024/2B.cpp
new file mode 100644
index 0000000..674f98f
--- /dev/null
+++ b/2024/2B.cpp
@@ -0,0 +1,61 @@
+#include <bits/stdc++.h>
+#include "readfile.hpp"
+
+int get_problem(const std::vector<int> &numbers) {
+	bool increasing = false, decreasing = false;
+	int prev = -1;
+	for (int i = 0; i < numbers.size(); ++i) {
+		if (prev == -1) {
+			prev = numbers[i];
+			continue;
+		}
+		if (prev < numbers[i])
+			increasing = true;
+		else if (prev > numbers[i])
+			decreasing = true;
+		if (std::abs(prev - numbers[i]) > 3 || prev == numbers[i] || increasing && decreasing || !increasing && !decreasing)
+			return i;
+		prev = numbers[i];
+	}
+	return -1;
+}
+
+
+int main(int argc, char const *argv[])
+{
+	int res = 0;
+	std::vector<std::string> file = readfile("2.in");
+	if (file.empty())
+		return 1;
+
+	for (const auto &line : file) {
+		std::istringstream iss(line);
+		std::vector<int> lv;
+		int n;
+		while (iss >> n) {
+			lv.push_back(n);
+		}
+		if (get_problem(lv) == -1) {
+			++res;
+			continue;
+		}
+
+		// not safe / strike 1
+		// try removing the problem number
+		for (int i = 0; i < lv.size(); ++i) {
+			std::vector<int> lv2;
+			for (int j = 0; j < lv.size(); ++j) {
+				if (j == i)
+					continue;
+				lv2.push_back(lv[j]);
+			}
+			if (get_problem(lv2) == -1) {
+				++res;
+				break;
+			}
+		}
+	}
+
+	// print
+	std::cout << res << std::endl;
+}
+\ No newline at end of file