1.基础，判断素数

#include <iostream>
#include <math.h>
using namespace std;

/*判断素数*/
int isprime(int number)
{
    if(number<2){
        return 0;
    }else{
        for(int i=2;i<=sqrt(number);i++){
            if(number % i == 0){
                return 0;
            }
        }
        return 1;
    }

}


int main()
{
    int number = 0;
    cin >> number;
    if(isprime(number)){
        cout << "the number is prime"<< endl;
    }else{
        cout << "the number is not prime" << endl;
    }
    return 0;
}