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  1. #include <iostream>
  2. #include <atomic>
  3. #include <cstdint>
  4.  
  5. int main()
  6. {
  7.     std::atomic<uint64_t> array[2];
  8.     std::atomic<int> pos;
  9.  
  10.     array[0] = ATOMIC_VAR_INIT(0);
  11.     array[1] = ATOMIC_VAR_INIT(0);
  12.     pos      = ATOMIC_VAR_INIT(0);
  13.  
  14.     //normal increment
  15.     array[pos]++;
  16.     pos++;
  17.  
  18.     //atomic increment
  19.     int fetchReturnArray = std::atomic_fetch_add(&array[pos], (uint64_t)1);
  20.     int fetchReturnPos   = std::atomic_fetch_add(&pos, 1);
  21.  
  22.     std::cout << "Array[0]         = " <<array[0]         <<std::endl;
  23.     std::cout << "fetchReturnArray = " <<fetchReturnArray <<std::endl;
  24.     std::cout << "Array[1]         = " <<array[1]         <<std::endl;
  25.  
  26.     std::cout << "fetchReturnPos   = " << fetchReturnPos <<std::endl;
  27.     std::cout << "Pos              = " << pos; 
  28. }
Success #stdin #stdout 0s 2896KB
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stdin
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Standard input is empty
stdout
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Array[0]         = 1
fetchReturnArray = 0
Array[1]         = 1
fetchReturnPos   = 1
Pos              = 2
https://ideone.com/7RqlwP
language:
C++14 (gcc 8.3)
created:
12 years ago
visibility:
public

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