#include <bits/stdc++.h>
#define GET_MACRO(a, b, c, NAME, ...) NAME
#define rep(...) GET_MACRO(__VA_ARGS__, rep3, rep2)(__VA_ARGS__)
#define rep2(i, a) rep3 (i, 0, a)
#define rep3(i, a, b) for (int i = (a); i < (b); i++)
#define repr(...) GET_MACRO(__VA_ARGS__, repr3, repr2)(__VA_ARGS__)
#define repr2(i, a) repr3 (i, 0, a)
#define repr3(i, a, b) for (int i = (b) - 1; i >= (a); i--)
template<class T1, class T2> inline bool chmin(T1 &a, T2 b) { return b < a && (a = b, true); }
template<class T1, class T2> inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
using namespace std;
typedef long long ll;

ll dp[20][2][2][20][2]; // less, 0-1, num 12, leading zero

pair<ll, ll> f(string S, bool less, bool onetwo) {
	if (S.length() <= 1) {
		int n = S[0] - '0';
		if (n <= 1) {
			return {0, 0};
		} else {
			return {0, 1};
		}
	}
	memset(dp, 0, sizeof(dp));
	int n = S.length();
	dp[0][0][0][0][0] = 1;
	rep (i, n) rep (j, 2) {
		rep (k, 2) rep (l, 19) rep (m, 2) {
			int lim = j ? 9 : S[i] - '0';
			rep (x, lim + 1) {
				if (onetwo && !m && x > 0 && x != 2) continue;
				if (onetwo && i == n - 1 && x != 1) continue;
				if (k == 0 && x == 1) {
					dp[i + 1][j || x < lim][1][l][m || x > 0] += dp[i][j][k][l][m];
				} else if (k == 1 && x == 1) {
					dp[i + 1][j || x < lim][1][l][m || x > 0] += dp[i][j][k][l][m];
				} else if (k == 1 && x == 2) {
					dp[i + 1][j || x < lim][0][l + 1][m || x > 0] += dp[i][j][k][l][m];
				} else {
					dp[i + 1][j || x < lim][0][l][m || x > 0] += dp[i][j][k][l][m];
				}
			}
		}
	}
	ll res1 = 0, res2 = 0;
	rep (j, 2) rep (k, 2) rep (l, 20) rep (m, 2) {
		if (j == 0 && less) continue;
		res1 += dp[n][j][k][l][m] * l;
		res2 += dp[n][j][k][l][m];
	}
	return {res1, res2 + 1};
}

int main() {
	string A, B;
	cin >> A >> B;
	ll ans = f(B, false, false).first - f(A, true, false).first;
	ans += f(B, true, true).second - f(A, true, true).second;
	cout << ans << endl;
	return 0;
}