反手就是一波欧拉筛，
忘记给0和1赋值为1坑死我了
#include<iostream>
#include<vector>
using namespace std;
const int N=1e5+10;
int vis[N];
int prime[N];
void getp(){
int cnt=0;
vis[0]=vis[1]=1;
for (int i = 2; i < N; ++i)
{
if(!vis[i]){
prime[cnt++]=i;
}
for (int j = 0; j<cnt&&i*prime[j]<N; ++j)
{
vis[i*prime[j]]=1;
if(i%prime[j]==0)
break;
}
}
}
int covert(int a, int radix){
int res=0;
while(a>0){
res = res*radix+(a%radix);
a/=radix;
}
return res;
}
int main(int argc, char const *argv[])
{
int a,b;
getp();
vector<string> ans;
while(cin>>a,a>=0){
cin>>b;
if(vis[a]||vis[covert(a,b)])
ans.push_back("No");
else
ans.push_back("Yes");
}
for (int i = 0; i < ans.size(); ++i)
{
cout<<ans[i];
if(i<ans.size()-1)
cout<<endl;
}
return 0;
}