/* _____ _ ____ _ |_ _| |__ ___/ ___| ___ _ __ | |_ _ __ ___ | | | '_ \ / _ \___ \ / _ \ '_ \| __| '__/ _ \ | | | | | | __/___) | __/ | | | |_| | | (_) | |_| |_| |_|\___|____/ \___|_| |_|\__|_| \___/ */ #include <bits/stdc++.h> // #pragma GCC optimize("O3") using namespace std; #define ll long long ll mod = 1e9+7; ll binpow(ll a, ll b) { ll res = 1; while (b>0) { if (b&1) res = (res*a)%mod; a = (a*a)%mod; b>>=1; } return res; } ll gcd(ll x, ll y) { if (y==0) return x; return gcd(y, x%y); } ll dp[20][11][11][2][2]; void cln() { for (int i=0 ; i<20 ; i++) { for (int j=0 ; j<11 ; j++) { for (int k=0 ; k<11 ; k++) { for (int q=0 ; q<2 ; q++) { for (int qq =0 ; qq<2 ; qq++) { dp[i][j][k][q][qq] = 0; } } } } } } ll cnt(ll x) { if (x==-1) return 0; cln(); dp[0][10][10][1][1] = 1; string s = to_string(x); vector<ll>v; v.push_back(-1); for (int i=0 ; i<s.size() ; i++) v.push_back(s[i]-'0'); for (int st=1 ; st<v.size() ; st++) { for (int i=0 ; i<=10 ; i++) { for (int j=0 ; j<=10 ; j++) { for (int k=0 ; k<=10 ; k++) { for (int j1=0 ; j1<=1 ; j1++) { for (int j2=0 ; j2<=1 ; j2++) { if (j2==1 and k==0) continue; if (k==10 and j2!=1) continue; if (k==10 and j2==1){ dp[st][j][k][((j1)&(v[st]==0))][1] += dp[st-1][i][j][j1][j2]; continue;} if (j1==1) { if (k==v[st]) { if (k!=j and k!=i) dp[st][j][k][1][0] += dp[st-1][i][j][j1][j2]; } if (k<v[st]) { if (k!=j and k!=i) dp[st][j][k][0][0] += dp[st-1][i][j][j1][j2]; } } else { if (k!=j and k!=i) dp[st][j][k][0][0] += dp[st-1][i][j][j1][j2]; } } } } } } } ll sum=0; for (int i=0 ; i<=10 ; i++) { for (int j=0 ; j<=10 ; j++) { for (int j1=0 ; j1<2 ; j1++) { for (int j2=0 ; j2<2 ; j2++) sum += dp[v.size()-1][i][j][j1][j2]; } } } // cout<<dp[1][10][10][0][1]<<endl; return sum; } void solve() { ll l,r; cin>>l>>r; cout<<cnt(r)-cnt(l-1); } int main() { // freopen ("input.txt","r",stdout); // freopen ("output.txt","w",stdout); ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); ll tt = 1; // cin>>tt; while (tt--) { solve(); } return 0; }