function Main(input) {
  var list = input.split("\n");
  var a = parseInt(list[0], 10);
  var e = parseInt(list[4], 10);
  var k = parseInt(list[5], 10);
  
  if (e-a>k) console.log(":(");
  else console.log("Yay!");
}
 
Main(require("fs").readFileSync("/dev/stdin", "utf8"));