import std.stdio, std.conv, std.string;

void main()
{
    auto D = readln().strip.to!int;
    switch(D)
    {
        case 25:
            writeln("Christmas");
        break;
        case 24:
            writeln("Christmas Eve");
        break;
        case 23:
            writeln("Christmas Eve Eve");
        break;
        case 22:
            writeln("Christmas Eve Eve Eve");
        break;
        default:
        break;
    }
}
