#include <iostream>
#include <cstdio>
using namespace std;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
#ifndef ONLINE_JUDGE
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
int x, y;
cin >> x >> y;
bool found = false;
for (int i = x; i <= y; i++) {
bool c = true;
int a = i;
int b = i;
while (b != 0) {
a = b % 10;
b /= 10;
if (a == 4 || a == 7) {
c = true;
} else {
c = false;
break;
}
}
if (c == true) {
cout << i << " ";
found = true;
}
}
if (found == false) {
cout << -1 << endl;
}
return 0;
}
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