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  1. #include <iostream>
  2.  
  3. int divisorsSum( int x )
  4. {
  5.     int result = 1;
  6.     int upperLimit = x / 2 + 1;
  7.  
  8.     for ( int d = 2; d < upperLimit; ++d )
  9.     {
  10.         if ( x % d == 0 )
  11.         {
  12.             result += d;
  13.             result += (x / d);
  14.             upperLimit = (x / d);
  15.         }
  16.     }
  17.  
  18.     return result;
  19. }
  20.  
  21. void findNFriends( int n )
  22. {
  23.     int findedCount = 0;
  24.     for ( int f = 220; ; ++f )
  25.     {
  26.         int s = divisorsSum( f );
  27.         if ( (f < s) && (f % 2 == s % 2) && (f == divisorsSum( s )) )
  28.         {
  29.             ++findedCount;
  30.             std::cout << "(" << f << ", " << s << ")" << std::endl;
  31.  
  32.             if ( findedCount >= n ) break;
  33.         }
  34.     }
  35. }
  36.  
  37. int main() {
  38.     findNFriends(14);
  39.     return 0;
  40. }
Success #stdin #stdout 11.85s 2724KB
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stdin
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Standard input is empty
stdout
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(220, 284)
(1184, 1210)
(2620, 2924)
(5020, 5564)
(6232, 6368)
(10744, 10856)
(12285, 14595)
(17296, 18416)
(63020, 76084)
(66928, 66992)
(67095, 71145)
(69615, 87633)
(79750, 88730)
(100485, 124155)
https://ideone.com/6XwxCw
language:
C++ (gcc 8.3)
created:
13 years ago
visibility:
public

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