function main(i) {
  i = i.split('\n');
  var a = Number(i[0]), b = Number(i[1]), c = Number(i[2]), d = Number(i[3]), e = Number(i[4]), k = Number(i[5]);
  if (k >= e - a) {
    console.log('Yay!');
  } else {
    console.log(':(');
  }
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));