'commit'

TangDou/AcWing_TiGao/T5/ShaiSuShu/1292_0.cpp

@@ -0,0 +1,38 @@
+#include <iostream>
+#include <cmath>
+using namespace std;
+bool is_prime(int num) {
+    if (num < 2) {
+        return false;
+    }
+
+    for (int i = 2; i <= sqrt(num); i++) {
+        if (num % i == 0) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+int main() {
+    int n = 100; // n的值为100
+
+    int prime_count = 0; // 质数个数的计数器
+
+    for (int i = 2; i <= n; i++) {
+        if (is_prime(i)) {
+            prime_count++;
+        }
+    }
+
+    cout << log(n) << endl;
+
+    cout << "质数个数: " << prime_count << endl;
+
+    double estimated_count = (n / log(n)); // 使用质数个数定理估计质数的个数
+
+    cout << "质数个数定理估计值: " << estimated_count << endl;
+
+    return 0;
+}