zju pat 1015

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

bool prime(int num)
{
int i;
if(num ==0 || num ==1)
return false;
for(i=2;i<=sqrt(double(num));i++)
{
if(num % i ==0)
return false;
}
return true;
}

int convert(int n,int d)
{
int sum =0;
while(n!=0)
{
sum = sum*d + n %d;
n = n/d;
}
return sum;
}

int main()
{
int n,d;
while(cin>>n)
{
if(n<0)
break;
cin>>d;
if(prime(n) && prime(convert(n,d)))
cout<<"Yes"<<endl;
else
cout<<"No"<<endl;
}
return 0;
}