#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
int n;
int b[205]={-20,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1};
int main()
{
cin>>n;
cout<<b[n]<<endl;
return 0;
}