std::clock_t
From cppreference.com
                    
                                        
                    
                    
                                                            
                    | Defined in header  <ctime> | ||
| typedef /* unspecified */ clock_t; | ||
Arithmetic type capable of representing the process running time of implementation-defined range and precision.
[edit] See also
| returns raw processor clock time since the program is started (function) | |
| number of processor clock ticks per second (macro constant) | |
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C documentation for clock_t
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