func_code_string: #include <bits/stdc++.h>   using namespace std;   long long solve(int n) {     int x = n;     long long cnt = 0, ans = 0;     while (x) {       x = x / 10;       cnt++;     }     ans = n * cnt + cnt - 1;     int k = 1;     for (int i = 0; i < cnt - 1; i++) {       k = k * 10;       ans = ans - k;     }     return ans;   }   int main() {     int n;     long long ans;     scanf( %d , &n);     if (n < 10) {       cout << n;     } else {       cout << solve(n);     }     return 0;   }   