#include<cstdlib>
#include<cassert>
#include<cstdio>
#include<vector>
#include<queue>
#include<map>
#include<cctype>
#include<string>
#include<cstring>
#include<algorithm>
#include<unordered_set>
#include<unordered_map>
using namespace std;

#define fisier 0
#define consola 0

#if fisier
 #include<fstream>
 ifstream cin("fisier.in");
 ofstream cout("fisier.out");
#else
 #include<iostream> 
#endif


long long n,sol,s;

int main(){
    cin>>n;
    
    if(n<=2) sol=1;
    else{
    	s=(n*(n+1))/2;
    	sol=0;
    	if(n&1 || s&1) sol+=n/2+1; 
	}
    
    sol+=15;
    cout<<sol;
    
    
    #if fisier
     cin.close();
     cout.close();
    #endif
    
    #if consola
     system("pause");
    #endif
    return 0;
}