[1122] - C语言实验——判断素数（循环结构）(C++版本)

#include<iostream>
using namespace std;
int main()
{
    int n,i;
    cin>>n;
    if(n==1)
        cout<<"This is not a prime."<<endl;
    else if(n==2)
        cout<<"This is a prime."<<endl;
    else if(n<=1000000&&n>=3)
    {
        for(i=2;i<n;i++)
        {
            if(n%i==0)
                break;
        }
        if(i<n)
        cout<<"This is not a prime."<<endl;
        else
            cout<<"This is a prime."<<endl;
    }
    return 0;
}