#include <bits/stdc++.h>
using namespace std;
#define int __int128
//#define pb push_back
int inf = 1e18;
const int mod = 1e9 + 7;
const int N = 1e5 + 5;
int read() {
string s;
cin >> s;
int va = 0;
for(auto x : s) {
va = va *10 + (x-'0');
}
return va;
};
void prin(int va) {
if(va == 0) return cout << 0 << '\n', void();
string s;
while(va > 0) {
s += va%10 + '0';
va/= 10;
}
reverse(s.begin(), s.end());
cout << s << '\n';
}
vector<int> pw(22, 1);
int dig(int &va, int id){
return (va / pw[id]) %10;
};
int sz(int x){
if(x <= 0) return 0;
int len = 18;
while(x / pw[len] == 0)len--;
return len;
};
map<array<int,4>, int> mp;
int get (int la, int lla, int id, bool ispr, int lim) {
if(lim < 0)return 0;
if(id < 0)return 1;
if(mp[{la, lla, id, ispr}]) return mp[{la, lla, id, ispr}];
int res = 0;
int x = dig(lim, id);
for(int i = 0; i < 10; i ++ ){
if(i == la || i == lla) continue;
if(ispr && i > x)continue;
if(ispr && i == x)
res += get(i, la, id-1, 1, lim);
else res += get(i, la, id-1, 0, lim);
}
//cout << la << ' ' << lla << ' ' << id << ' ' << ispr << ' ' << res << '\n';
//cout << lim << ' ' << id << ' ' << x << '\n';
return mp[{la, lla, id, ispr}] = res;
};
void solve(){
for(int i = 1; i < 22; i ++ ) pw[i] = pw[i-1] * 10;
auto ok = [&] (int x) -> bool {
int len = sz(x);
for(int i = 0; i + 1 <= len; i ++ ) {
if(dig(x, i) == dig(x, i+1))return 0;
if(i + 2 <= len && dig(x, i) == dig(x, i + 2))return 0;
}
return 1;
};
int l, r;
l = read();
r = read();
if(r - l < 200000) {
int ans = 0;
for(int i = l; i <= r; i ++ ) {
ans += ok(i);
};
prin(ans);
return;
};
r = get(-1, -2, sz(r), 1, r);
mp.clear();
prin(r - get(-4, -5, sz(l), 1, l) + ok(l));
};
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
int tt = 1;
//cin >> tt;
while(tt -- ){
solve();
};
};
