#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 26;
int64_t DP[MAX_N][11][11];
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
int64_t l, r;
cin >> l >> r;
r++;
string _L = to_string(l), _R = to_string(r);
reverse(_L.begin(), _L.end());
reverse(_R.begin(), _R.end());
while (_L.size() < MAX_N - 1) {
_L += '0' + 10;
}
while (_R.size() < MAX_N - 1) {
_R += '0' + 10;
}
reverse(_L.begin(), _L.end());
reverse(_R.begin(), _R.end());
auto Count = [](string R) {
memset(DP, 0, sizeof DP);
bool good = true;
for (int i = 2; i < MAX_N - 1; i++) {
if ((R[i - 1] != '0' + 10) && (R[i - 1] == R[i - 2] || (i >= 3 && R[i - 1] == R[i - 3]))) {
good = false;
}
for (int A = 0; A <= 10; A++) {
for (int B = 0; B <= 10; B++) {
for (int C = 0; C < 10; C++) {
if (A == C || B == C) {
continue;
}
if (R[i] != '0' + 10 && C < R[i] - '0' && A == R[i - 2] - '0' && B == R[i - 1] - '0' && good) {
DP[i + 1][B][A == 10 && B == 10 && C == 0 ? 10 : C]++;
}
DP[i + 1][B][A == 10 && B == 10 && C == 0 ? 10 : C] += DP[i][A][B];
}
}
}
}
int64_t ans = 0;
for (int A = 0; A <= 10; A++) {
for (int B = 0; B <= 10; B++) {
ans += DP[MAX_N - 1][A][B];
}
}
return ans;
};
cout << Count(_R) - Count(_L) << "\n";
}
