#include <bits/stdc++.h>
using namespace std;
int main()
{/// Standing in The hall of Fame
    ios_base::sync_with_stdio(false) , cin.tie(NULL) , cout.tie(NULL);
    int a[5] , k;
    for(int i = 0 ; i < 5 ; i++)
        cin >> a[i];
    cin >> k;
    for(int i = 4 ; i > 0 ; i--)
        for(int j = i-1 ; j >= 0 ; j--)
            if(a[i]-a[j] > k)
                return cout << ":(\n" , 0;
    cout << "Yay!\n";
    return 0;
}