import std.stdio, std.string, std.conv;
import std.typecons;
import std.algorithm, std.array, std.range, std.container;
import std.math;

void main() {
	auto a = readln.split[0].to!int;
	auto b = readln.split[0].to!int;
	auto c = readln.split[0].to!int;
	auto d = readln.split[0].to!int;
	auto e = readln.split[0].to!int;
	auto k = readln.split[0].to!int;
	if ( e-a > k ) writeln(":(");
	else writeln("Yay!");
}

