2024 day 2

2024/2/main-1.cpp

@@ -0,0 +1,29 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int main() {
+	ios::sync_with_stdio(0);
+	cin.tie(0);
+
+	int total = 0;
+	string line;
+	while (getline(cin, line) && !line.empty()) {
+		istringstream l(line);
+		vector<int> t;
+		while (!l.eof()) {
+			int x;
+			l >> x;
+			t.push_back(x);
+		}
+		int pos = (t[1] > t[0]) ? 1 : -1;
+		for (int i = 0; i < t.size() - 1; i++) {
+			int diff = (t[i + 1] - t[i]) * pos;
+			if (diff < 1 || diff > 3) {
+				goto next;
+			}
+		}
+		total++;
+	next:;
+	}
+	cout << total << '\n';
+}

2024/2/main-2.cpp

@@ -0,0 +1,47 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+bool check(const auto &t) {
+	int pos = (t[1] > t[0]) ? 1 : -1;
+	for (int i = 0; i < t.size() - 1; i++) {
+		int diff = (t[i + 1] - t[i]) * pos;
+		if (diff < 1 || diff > 3) {
+			return false;
+		}
+	}
+	return true;
+}
+
+int main() {
+	ios::sync_with_stdio(0);
+	cin.tie(0);
+
+	int total = 0;
+	string line;
+	while (getline(cin, line) && !line.empty()) {
+		istringstream l(line);
+		vector<int> t;
+		while (!l.eof()) {
+			int x;
+			l >> x;
+			t.push_back(x);
+		}
+		if (check(t)) {
+			total++;
+		} else {
+			for (int i = 0; i < t.size(); i++) {
+				vector<int> tt;
+				for (int j = 0; j < t.size(); j++) {
+					if (j == i)
+						continue;
+					tt.push_back(t[j]);
+				}
+				if (check(tt)) {
+					total++;
+					break;
+				}
+			}
+		}
+	}
+	cout << total << '\n';
+}