C++ 算法：统计两个整数之间素数的个数

#include using namespace std;

bool isPrime(int n) { if (n <= 1) { return false; } for (int i = 2; i * i <= n; i++) { if (n % i == 0) { return false; } } return true; }

int countPrimes(int A, int B) { int count = 0; for (int i = A; i <= B; i++) { if (isPrime(i)) { count++; } } return count; }

int main() { int A, B; cin >> A >> B; int count = countPrimes(A, B); cout << count << endl; return 0; }