add: 211231-CN

2112/211231-CN.cpp

@@ -0,0 +1,31 @@
+#include <iostream>
+#include <cmath>
+
+class Solution {
+public:
+	static bool checkPerfectNumber(int num) {
+		switch (num) {
+			case 6:
+			case 28:
+			case 496:
+			case 8128:
+			case 33550336:
+				return true;
+			default:
+				return false;
+		}
+	}
+};
+
+int main() {
+	for (int i = 1; i < 100000000; ++i) {
+		int s = 1;
+		int lim = int(std::sqrt(i + 0.50));
+		for (int j = 2; j <= lim; ++j)
+			if (i % j == 0)
+				s += j + i / j;
+		if (s == i)
+			std::printf("%d\n", i);
+	}
+	return 0;
+}

2112/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(2112)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2112 211231.cpp)
+ADD_EXECUTABLE(2112 211231-CN.cpp)