#include<iostream> #include<cstdio> #include<cstring> #include<cmath> using namespace std; int sum(int x){ int s=1; for(int i=2;i<=sqrt(x);i++){ if(x%i==0){ return 0; } } return 1; } int main(){ int n,c=0; cin>>n; for(int j=2;j<=n-2;j++){ if(sum(j)&&sum(j+2)){ cout<<j<<" "<<j+2<<endl; c++; } } if(c==0) cout<<"No"; return 0; }