#include "bits/stdc++.h"
using namespace std;
#define ll long long
#define mod 1000000007
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
ll n;
string s;
ll dp[20][2][11][11];
ll solve(ll ind, bool b, ll lst1, ll lst2) {
if(ind + 1 == n)
return 1;
if(dp[ind + 1][b][lst1][lst2])
return dp[ind + 1][b][lst1][lst2];
ll ans = 0;
if(b == 1) {
ll d = (s[ind + 1] - '0');
for(ll i = 0; i <= d; i++) {
if(i == lst1 || i == lst2)
continue;
ans += solve(ind + 1, (i == d), i, lst1);
}
}
else {
for(ll i = 0; i <= 9; i++) {
if(i == lst1 || i == lst2)
continue;
ans += solve(ind + 1, 0, i, lst1);
}
}
return dp[ind + 1][b][lst1][lst2] = ans;
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
string b;
ll a;
cin >> a >> b;
s = b;
n = s.size();
ll ans = solve(-1, 1, 10, 10);
a--;
if(a >= 0) {
memset(dp, 0, sizeof dp);
s = to_string(a);
n = s.size();
ans -= solve(-1, 1, 10, 10);
}
cout << ans;
return 0;
}
