#include <bits/stdc++.h>
using namespace std;

const int x[10] = {6, 2, 5, 5, 4, 5, 6, 3, 7, 6};
long long l, r;

long long getMatches(long long num) {
    long long count = 0;
    while (num > 0) {
        count += x[num % 10];
        num /= 10;
    }
    return count;
}

int main() {
	cin >> l >> r;
	vector<long long> sum;
	for(long long i = l;i <= r;i++){
		sum.push_back(getMatches(i));
	}
	long long last = l, max = 1;
	long long n = 0;
	for (long long i = l; i <= r; i++) {
		long long now = 0;
		long long vel = i;
		now = sum[i-l];
		if (now != last) {
			if (n > max) {
				max = n;
			}
			n = 1;
		} else {
			n++;
		}
		last = now;
	}
	cout << max;
	return 0;
}