input = require('fs').readFileSync('/dev/stdin', 'utf8')
lines = input.split('\n')
a = lines.shift() * 1
b = lines.shift() * 1
c = lines.shift() * 1
d = lines.shift() * 1
e = lines.shift() * 1
k = lines.shift() * 1
console.log(e - a <= k ? 'Yay!' : ':(' )