function main(input) {
    const args = input.split(' ');
    const D = parseInt(args[0], 10);

    if (D === 25) {
        console.log("Christmas");
    }
    else if (D === 24) {
        console.log("Christmas Eve");
    }
    else if(D === 23) {
        console.log("Christmas Eve Eve");
    }
    else if(D === 22) {
        console.log("Christmas Eve Eve Eve");
    }
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'));
