function Main(input){
var an = input.split("\n");
var k = an[5];
an.pop();
for(i=0;i<=4;i++){
  an[i] = parseInt(an[i],10);
}
for(j=0;j<=4;j++){
  for(s=0;s<=4;s++){
    if(j<=s){
      continue;
    }else{
      var dist = Math.abs(an[j] - an[s]);
      var judge = dist <= k;// true or false
      if(judge==false){
        console.log(":(");
        break;
      }
      if(judge==true&&j==4&&s==3){
        console.log("Yay!");
      }
    }
  }
  if(judge==false){
    break;
  }
}
}
  Main(require('fs').readFileSync('/dev/stdin','utf8'));