Problem:
﻿Score: 100 points

Problem Statement

In AtCoder city, there are five antennas standing in a straight line. They are called Antenna A, B, C, D and E from west to east, and their coordinates are a, b, c, d and e, respectively.

Two antennas can communicate directly if the distance between them is k or less, and they cannot if the distance is greater than k.

Determine if there exists a pair of antennas that cannot communicate directly.

Here, assume that the distance between two antennas at coordinates p and q (p < q) is q - p.

Constraints

a, b, c, d, e and k are integers between 0 and 123 (inclusive).

a < b < c < d < e

Input

Input is given from Standard Input in the following format:

a
b
c
d
e
k

Output

Print :( if there exists a pair of antennas that cannot communicate directly, and print Yay! if there is no such pair.

Sample Input 1

1
2
4
8
9
15

Sample Output 1

Yay!

In this case, there is no pair of antennas that cannot communicate directly, because:

the distance between A and B is 2 - 1 = 1

the distance between A and C is 4 - 1 = 3

the distance between A and D is 8 - 1 = 7

the distance between A and E is 9 - 1 = 8

the distance between B and C is 4 - 2 = 2

the distance between B and D is 8 - 2 = 6

the distance between B and E is 9 - 2 = 7

the distance between C and D is 8 - 4 = 4

the distance between C and E is 9 - 4 = 5

the distance between D and E is 9 - 8 = 1

and none of them is greater than 15. Thus, the correct output is Yay!.

Sample Input 2

15
18
26
35
36
18

Sample Output 2

:(

In this case, the distance between antennas A and D is 35 - 15 = 20 and exceeds 18, so they cannot communicate directly.
Thus, the correct output is :(.

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            var sc = new Scanner();
            int[] a = new int[5];
            for (int i = 0; i < a.Length; i++) a[i] = sc.NextInt();
            int k = sc.NextInt();

            for (int i = 0; i < a.Length; i++)
                for (int j = i + 1; j < a.Length; j++)
                {
                    if (a[j] - a[i] > k)
                    {
                        Console.WriteLine(":(");
                        return;
                    }
                }

            Console.WriteLine("Yay!");
        }
    }

    class Scanner
    {
        int index = -1;
        string[] buf;

        public Scanner()
        {
        }

        public int NextInt()
        {
            CheckNext();
            return int.Parse(buf[index++]);
        }

        public string NextString()
        {
            CheckNext();
            return buf[index++];
        }

        private void CheckNext()
        {
            if (index >= 0 && index < buf.Length) return;

            buf = Console.ReadLine().Split(' ');
            index = 0;
        }
    }
}