题解 | #判断一个数是不是质数#

#include <iostream>

int main() {
    int num;

    std::cin >> num;

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

    if (isPrime) {
        std::cout << "是质数" << std::endl;
    } else {
        std::cout << "不是质数" << std::endl;
    }

    return 0;
}