#include<bits/stdc++.h>
// #pragma GCC target ("avx,avx2,fma")
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
typedef long long ll;
typedef long double ld;
#define SPEED ios_base::sync_with_stdio(false); cin.tie(0), cout.tie(0)
#define rall(v) (v).rbegin(),(v).rend()
#define all(v) (v).begin(),(v).end()
#define OK cerr<<"OK"<<endl<<flush
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define F first
#define S second
#define y0 jahdakdh
#define y1 jahsadakdakdh
#define endl '\n'
using namespace std;
const ll MOD=1e9+7;
// mt19937 rng(std::chrono::system_clock::now().time_since_epoch().count());
ll a, b;
ll ans;
bool check(int x)
{
string s=to_string(x);
s+='-';
for(int i=0; i<(int)s.length()-2; i++)
{
if(s[i]==s[i+1] or s[i]==s[i+2])
return 0;
}
return 1;
}
int main()
{
SPEED;
cin>>a>>b;
for(int i=a; i<=b; i++)
{
ans+=check(i);
}
cout<<ans<<endl;
return 0;
}
