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 Rust (1.15.1) (judge verdict: Wrong Answer)

use std::io;

fn printnum(x: i32){
    println!("{}", x);
}

fn sum(x: i32, y: i32) -> i32{
    x + y
}

fn read() -> i32{
    let mut x = String::new();
    io::stdin().read_line(&mut x).expect("read_line error");
    let x = x.trim().parse().expect("parse error");
    x
}

fn main() {
    let mut a = [0; 5];
    let mut idx = 0;
    loop {
        if idx == a.len() { break; }
        a[idx] = read();
        idx = idx + 1;
    }
    let k = read();
    let mut f = true;
    idx = 1;
    loop {
        if idx == a.len() { break; }
        if a[idx] - a[idx - 1] >= k {
            f = false;
            break;
        }
        idx = idx + 1;
    }
    println!("{}", if f { "Yay!" } else { ":(" });
}