#include <iostream>
#include <bits/stdc++.h>
#include <deque>
#include <vector>
#include<cstdio>
#include<string>
using namespace std;
int main()
{
    int a,b,c,d,e,k,z=0;
    cin>>a>>b>>c>>d>>e>>k;
    if(b-a>k) c++;
    else if(c-a>k) z++;
    else if(d-a>k) z++;
    else if(e-a>k) z++;
    else if(c-b>k) z++;
    else if(d-b>k) z++;
    else if(e-b>k) z++;
    else if(d-c>k) z++;
    else if(e-c>k) z++;
    else if(e-d>k) z++;
    if(z==0) cout<<"Yay!";
    else cout<<":(";
}
