#include<bits/stdc++.h>
using namespace std;
int n; 
int main(){
cin>>n;
if(n<0)cout<<n-1;
else if(n==0)cout<<0;
else cout<<n+1;
   return 0;
}
/**************************************************************
	Problem: 1038
	User: jiangyuanfeng
	Language: C
	Result: Compile Error
****************************************************************/