#include<bits/stdc++.h> using namespace std; #define int long long #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define sz(x) ((int)x.size()) #define sumof(x) accumulate(all(x), 0ll) int f[20][2][20][100]; int sus(const string &s, int id, bool smaller, int dig, int lst){ if (f[id][smaller][dig][lst]!=-1) return f[id][smaller][dig][lst]; if (id==sz(s)) return f[id][smaller][dig][lst]=1; int res=0; for (int i=0; i<=(smaller?9:s[id]-'0'); ++i){ if (dig && i==lst%10) continue; if (dig>=2 && i==lst/10) continue; res+=sus(s, id+1, smaller|(i<s[id]-'0'), dig+(dig || i), (lst%10)*10+i); } return f[id][smaller][dig][lst]=res; } int calc(int x){ if (x<0) return 0; stringstream ss; string s; ss << x; ss >> s; memset(f, -1, sizeof f); return sus(s, 0, 0, 0, 0); } void solve(int tc){ // cout << "Case #" << tc << ": "; int l, r; cin >> l >> r; cout << calc(r)-calc(l-1); } int32_t main(){ ios_base::sync_with_stdio(false); cin.tie(nullptr); int ntests=1; // cin >> ntests; for (int i=1; i<=ntests; ++i) solve(i); return 0; }