std:: clock_t

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Utilities library
General utilities
Relational operators (deprecated in C++20)
Defined in header <ctime>
typedef /* unspecified */ clock_t ;

Arithmetic type capable of representing the process running time of implementation-defined range and precision.

See also

returns raw processor clock time since the program is started
(function)
number of processor clock ticks per second
(macro constant)
C documentation for clock_t