func_code_string: #include <bits/stdc++.h>   using namespace std;   const int inf = 0;   const double eps = 0;   const int ms = 0;   const int md = 0;   const int MAX_N = 1e5 + 5;   const int MAX_L = 20;   const long long MOD = 1e9 + 7;   const long long INF = 1e9 + 7;   long long mpow(long long k) {     long long ans = 1;     while (k > 0) {       ans *= 10;       k--;     }     return ans;   }   long long countNines(long long n) {     long long ans = 0;     while (n > 0) {       if (n % 10 == 9) {         ans++;       } else         break;       n /= 10;     }     return ans;   }   int main() {     long long p, d;     cin >> p >> d;     int k = 1;     long long ans = -1;     while ((p - p % mpow(k) - 1) > 0) {       if ((p - p % mpow(k) - 1) >= p - d) {         ans = p - p % mpow(k) - 1;       }       k++;     }     if (countNines(ans) > countNines(p))       cout << ans << endl;     else       cout << p << endl;     return 0;   }   