#include <iostream>
using namespace std;
int main()
{
int x,y;
cin>>x;
if(x>=10)
{
y=x-1;
cout<<"y"<<y<<endl;
}
else if(1<x<10)
{
y=2*x+1;
cout<<"y"<<y<<endl;
}
else if(x<=1)
{
y=x-1;
cout<<"y"<<y<<endl;
}
return 0;
}