#pragma GCC optimize("O3") #pragma GCC optimize ("unroll-loops") // #pragma GCC target("avx2") #include <bits/stdc++.h> #define ll long long #define ull unsigned ll #define ld long double #define all(v, l) v.begin() + l, v.end() #define rall(v, l) v.rbegin(), v.rend() - l #define pb push_back #define rsz resize #define fi first #define se second #define LMAX LLONG_MAX #define LMIN LLONG_MIN #define IMAX INT_MAX #define IMIN INT_MIN #define endl "\n" #define newline cout << endl; using namespace std; // structs // globals // variables ll l, r; string A, B; // iterators int i; // notes /* -stuff you should look for- * int overflow, array bounds * special cases (n=1?) * do something instead of nothing and stay organized * WRITE STUFF DOWN * DON'T GET STUCK ON ONE APPROACH continue - skip the rest in the loop */ // functions ll GCD(ll numeroune, ll numerodeux); ll LCM(ll numeroune, ll numerodeux); ll power(ll numeroune, ll numerodeux); void solve() { cin >> l >> r; A = '*' + to_string(l - 1), B = '*' + to_string(r); ll dp[21][11][11][2]; function<ll(string, int, int, int, bool)> f = [&](string s, int k, int lst1, int lst2, bool tight) { if (k == (int)s.size()) { return 1LL; } if (dp[k][lst1][lst2][tight] != -1) { return dp[k][lst1][lst2][tight]; } ll sum = 0LL; for (char c = '0'; c <= (tight ? s[k] : '9'); c++) { if (lst1 == 10 && lst2 == 10 && c == '0') { auto temp = (tight && s[k] == '0' ? tight : false); sum += f(s, k + 1, lst1, lst2, temp); continue; } if ((c - '0') == lst1 || (c - '0') == lst2) { continue; } sum += f(s, k + 1, (c - '0'), lst1, (tight && s[k] == c)); } return dp[k][lst1][lst2][tight] = sum; }; memset(dp, -1LL, sizeof(dp)); ll temp1 = f(B, 1, 10, 10, 1); memset(dp, -1LL, sizeof(dp)); ll temp2 = (!l ? 0 : f(A, 1, 10, 10, 1)); cout << temp1 - temp2; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); int t = 1; // cin >> t; while (t--) { solve(); newline } } ll GCD(ll numeroune, ll numerodeux) { if (!numeroune) { return numerodeux; } return GCD(numerodeux % numeroune, numeroune); } ll LCM(ll numeroune, ll numerodeux) { return numeroune * numerodeux / GCD(numeroune, numerodeux); } ll power(ll numeroune, ll numerodeux) { ll res = 1; while (numerodeux) { if (numerodeux & 1) { res *= numeroune; } numeroune *= numeroune; numerodeux >>= 1; } return res; } /* $$$$$$$$\ $$$$$$$$\ $$ _____|\____$$ | $$ | $$ / $$$$$\ $$ / $$ __| $$ / $$ | $$ / $$$$$$$$\ $$$$$$$$\ \________|\________| */