C++实现素数筛选法

#include <iostream> #include <vector>  using namespace std;  void sieveOfEratosthenes(int n) {     vector<bool> isPrime(n+1, true);          for (int p = 2; p*p <= n; p++) {         if (isPrime[p]) {             for (int i = p*p; i <= n; i += p) {                 isPrime[i] = false;             }         }     }          for (int p = 2; p <= n; p++) {         if (isPrime[p]) {             cout << p << " ";         }     } }  int main() {     int n;     cout << "Enter a number: ";     cin >> n;          cout << "Prime numbers up to " << n << " are: ";     sieveOfEratosthenes(n);          return 0; } 

此代码实现了素数筛选法，输出小于等于给定数n的所有素数。