#include<iostream>
using namespace std;
int main(){
int n;
cin>>n;
int sum;
for(int counter=4;counter<=n;counter++){
sum=counter;
}
cout<<sum<<endl;
return 0;
}
I2luY2x1ZGU8aW9zdHJlYW0+CnVzaW5nIG5hbWVzcGFjZSBzdGQ7CiAKaW50IG1haW4oKXsKIAoJaW50IG47CgljaW4+Pm47CiAKCWludCBzdW07Cglmb3IoaW50IGNvdW50ZXI9NDtjb3VudGVyPD1uO2NvdW50ZXIrKyl7CgkJc3VtPWNvdW50ZXI7Cgl9CiAKCWNvdXQ8PHN1bTw8ZW5kbDsKIAoJcmV0dXJuIDA7Cn0=