fork download
copy 
  1. #include <iostream>
  2.  
  3. const int kThreeNum = 3;
  4. const int kSixNum = 6;
  5. const int kNineNum = 9;
  6.  
  7. int countDigits(int n, int x) 
  8. {
  9.     int count = 0;
  10.     int factor = 1;
  11.  
  12.     while (factor <= n) 
  13.     {
  14.         int lower = n % factor;
  15.         int current = (n / factor) % 10;
  16.         int higher = n / (factor * 10);
  17.  
  18.         if (current > x) 
  19.         {
  20.             count += (higher + 1) * factor;
  21.         } 
  22.         else if (current == x) 
  23.         {
  24.             count += higher * factor + (lower + 1);
  25.         } 
  26.         else 
  27.         {
  28.             count += higher * factor;
  29.         }
  30.  
  31.         factor *= 10;
  32.     }
  33.  
  34.     return count;
  35. }
  36.  
  37. int countClapsInRange(int startNum, int finishNum, int x) 
  38. {
  39.     return countDigits(finishNum, x) - countDigits(startNum - 1, x);
  40. }
  41.  
  42. int main() 
  43. {
  44.     int startNum = 0, finishNum = 0;
  45.     std::cin >> startNum >> finishNum;
  46.  
  47.     int ret = countClapsInRange(startNum, finishNum, kThreeNum) + 
  48.     	countClapsInRange(startNum, finishNum, kSixNum) + 
  49.     	countClapsInRange(startNum, finishNum, kNineNum);
  50.  
  51.     std::cout << ret;
  52.  
  53.     return 0;
  54. }
  55.  
Success #stdin #stdout 0.01s 5280KB
comments (?)
stdin
copy 
999999 10000000
stdout
copy 
19200006
https://ideone.com/5q6mub
language:
C++14 (gcc 8.3)
created:
12 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!