import std.stdio, std.string, std.conv, std.array, std.range, std.algorithm;

void main() {
  long a, b, c, d, e, k;
  readf("%d\n%d\n%d\n%d\n%d\n%d\n", &a, &b, &c, &d, &e, &k);

  if (e - a <= k) {
    writeln("Yay!");
  } else {
    writeln(":(");
  }

}
