#include #include #include #include #include #include #include #include #include #include #include #include #include #define repd(i,a,b) for (int i=(a);i<(b);i++) #define rep(i,n) repd(i,0,n) #define var auto #define mod 1000000007 #define inf 2147483647 #define nil -1 typedef long long ll; using namespace std; inline int input(){ int a; cin >> a; return a; } template inline void output(T a, int p) { if(p){ cout << fixed << setprecision(p) << a << "\n"; } else{ cout << a << "\n"; } } int ord(ll n){ ll a = 1; int ret = 0; while (1) { a *= 10; if (a > n) { break; } ret++; } return ret; } ll power(int ord){ ll a = 1; rep(i, ord){ a *= 10; } return a; } ll cnt_x12x(ll n){ ll ret = 0; rep(i, ord(n) + 1){ if (n % power(i + 2) >= 12 * power(i) && n % power(i + 2) < 13 * power(i)) { ret += n % power(i + 2) - 12 * power(i) + 1; } ret += (n - 13 * power(i) + power(i + 2)) / power(i + 2) * power(i); } return ret; } ll cnt_2x1(ll n){ ll ret = 0; repd(i, 2, ord(n) + 1){ ret += power(i - 2); } // cout << "cnt:" << n << ", " << ret << endl; if (n >= 2 * power(ord(n)) + 1 && ord(n)) { ret += min(power(ord(n) - 1), (n - (2 * power(ord(n)) + 1)) / 10 + 1); } return ret; } // end of template int main() { cin.tie(0); // source code ll A, B; cin >> A >> B; // cout << "debug: " << cnt_x12x(A) << ", " << cnt_x12x(B) << ", " << cnt_2x1(A) << ", " << cnt_2x1(B) << endl; ll ret = cnt_x12x(B) - cnt_x12x(A - 1) + cnt_2x1(B - 1) - cnt_2x1(A - 1); if (A == 1 && B >= 2) { ret++; } output(ret, 0); return 0; }