#include<iostream.h>
#include<math.h>
void main()
{
cout<<"input the number:";
int n;
cin>>n;
int j,leap=1,i;
for(i=1;i<=n;i++)
{
for(j=1;j<=sqrt(i);j++)
{
if(i%j==0)
{
leap=0;
break;
}
}
if(leap)
{
cout<<i<<endl;
}
}
}