#include <bits/stdc++.h>
using namespace std;
#define int long long
//#define pb push_back
int inf = 1e18;
const int mod = 1e9 + 7;
const int N = 1e5 + 5;
vector<int> pw(19, 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 < 19; i ++ ) pw[i] = pw[i-1] * 10;
int l, r;
cin >> l >> r;
l--;
r = get(-1, -1, sz(r), 1, r);
mp.clear();
cout << r - get(-1, -1, sz(l), 1, l) + (l < 0) << '\n';
};
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
int tt = 1;
//cin >> tt;
while(tt -- ){
solve();
};
};
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