c++ extern c

c++ extern c

  

   #include 
   <
   cstdlib
   >
   
#include 
   <
   fstream
   >
   
#include 
   <
   iomanip
   >
    
#include 
   <
   iostream
   >
    


   extern
    
   "
   C
   "
    {
#include 
   <
   sys
   /
   time.h
   >
   
#include 
   <
   unistd.h
   >
   
}

   using
    
   namespace
    std;


   //
    === FUNCTION ======================================================================

   //
    Name: main

   //
    Description: main function

   //
    =====================================================================================
   

    
   int
   
main ( 
   int
    argc, 
   char
    
   *
   argv[] )
{
 
   int
    i 
   =
    
   0
   , j 
   =
    
   0
   ;
 
   struct
    timeval tv1, tv2;
 
   double
    sec 
   =
    
   0
   ;
 gettimeofday(
   &
   tv1, 
   0
   ); 
 
   for
   (i 
   =
    
   0
   ; i 
   <
    
   1000000000
    ; i
   ++
   )
 {
 j
   ++
   ;
 }
 cout 
   <<
    j 
   <<
    endl;
 gettimeofday(
   &
   tv2, 
   0
   );
 sec 
   =
    (
   double
   )(tv2.tv_sec 
   -
    tv1.tv_sec) 
   +
    (
   double
   )(tv2.tv_usec 
   -
    tv1.tv_usec) 
   /
    
   1000000
   ;
 printf(
   "
   time1: %f\n
   "
   , sec);
 cout 
   <<
    sec 
   <<
   endl;
 
   return
    EXIT_SUCCESS;
} 
   //
    ---------- end of function main ----------