日志9
质数判断
#include<iostream>
#include<cmath>
using namespace std;
int main()
{
long long a,b;
while (cin >> a) {
bool z = true;
if (a == 1) {
cout << "No" << endl;//1不是质数
continue;
}
for (long long i = 2; i <= sqrt(a); i++) {//让数a除i到a的平方根，若余数为零则不是
b = a % i;
if (b == 0) {
cout << "No" << endl;
z = false;
break;
}
}
if (z) {
cout << "Yes" << endl;
}
}
return 0;
}