找出不大于n的素数对个数的C++代码实现

```cpp #include <iostream> using namespace std; int n, num; bool prime(int n) { if (n < 2) return false; for (int i = 2; i * i <= n; i++) { if (n % i == 0) return false; } return true; } int main() { cin >> n; for (int i = 2; i <= n - 2; i++) { if (prime(i) && prime(i + 2)) { num++; } } cout << num << endl; return 0; } ``` ######[AI问答 | 181点数解答 | 2026-05-16 19:14:40]