func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long A = 100000000000000LL, N = 300005;   long long p, d, limit;   long long cal(long long p) {     int x = 0;     if (p % 10 != 9) return 0;     while (p % 10 == 9) {       x++;       p /= 10;     }     return x;   }   int main() {     cin >> p >> d;     limit = p - d;     long long j = p;     long long length = log10(p) + 1;     long long initial = cal(p);     int i = 0;     long long powerr = 10;     while (true) {       j = p - p % powerr - 1;       if (j == -1) break;       if (j < limit) break;       powerr *= 10;     }     powerr /= 10;     j = p - p % powerr - 1;     if (j < limit) j = p;     if (j >= limit and powerr == 1) j = p;     if (initial >= (log10(powerr))) j = p;     cout << j;   }   