func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MOD = 1e9 + 7;   using namespace std;   int num[1001];   long long n;   long long check(long long k) {     long long p = 0, v = 0;     long long t = n;     while (t) {       if (t >= k) {         p += k;         t -= k;       } else {         p += t;         t = 0;       }       v += t / 10;       t -= t / 10;     }     if (v <= p)       return 1;     else       return 0;   }   int main() {     cin >> n;     long long l = 1;     long long r = 1e18;     long long ans = 0;     while (l <= r) {       long long mid = (l + r) / 2;       if (check(mid)) {         ans = mid;         r = mid - 1;       } else {         l = mid + 1;       }     }     cout << ans << endl;   }   