import std.stdio, std.conv, std.array;

void main()
{
    int N;
    readf("%d", &N);
  if(N == 25){
  	writeln("Christmas");
  }
 if(N == 24){
  	writeln("Christmas Eve");
  }
    if(N == 23){
  	writeln("Christmas Eve Eve");
  }
    if(N == 22){
  	writeln("Christmas Eve Eve Eve");
  }
    
  
  
}