#include <bits/stdc++.h>
using namespace std;
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
int n;
long long k;
cin >> n >> k;
vector<long long> dp(n + 1);
dp[0] = 1;
dp[1] = 2;
for (int i = 2; i <= n; i++)
dp[i] = dp[i - 2] + dp[i - 1];
if (k > dp[n])
{
cout << "Flowers\n";
return 0;
}
while (n >= 2)
{
if (k <= dp[n - 2])
{
cout << "47";
n -= 2;
}
else
{
cout << "7";
k -= dp[n - 2];
n--;
}
}
if (n == 1)
{
if (k == 1)
cout << "4";
else
cout << "7";
}
cout << "\n";
return 0;
}
