Output running time (accurate to microseconds)

For code that requires performance, it is necessary to output the program running time and require high accuracy. The following code segment implements this function.

Note: It is only used in Linux because of <sys/time. h>.

1 # include <sys/time. h> 2 # include <iostream> 3 4 using namespace STD; 5 6 int main (INT argc, char ** argv) 7 {8 // time used for statistics 9 unsigned int untimeuse; 10 11 struct timeval ststarttime; 12 struct timeval stendtime; 13 14 gettimeofday (& ststarttime, null); 15 16 int I = 10000; 17 while (I --> 0 ); 18 19 gettimeofday (& stendtime, null); 20 untimeuse = 1000000 * (stendtime. TV _sec-ststarttime. TV _sec) + 21 stendtime. TV _usec-ststarttime. TV _usec; 22 23 cout. SETF (ios_base: fixed); 24 cout <"use time:" <untimeuse/1000000.0 <"Sec" <Endl; 25 26 return 0; 27}

Output result:

Output running time (accurate to microseconds)