获取程序运行时间

#include <stdio.h>
#include<sys/time.h>
#include<stdlib.h>
void play()
{
int i;
for(i=0;i<1000000;i++);
}
int main()
{
int diff;
struct timeval start,end;
gettimeofday(&start,0);
play();
gettimeofday(&end,0);
n=1000000 * (end.tv_sec-start.tv_sec)+end.tv_usec-start.tv_usec;
printf("do %d microsecond",n);

}

或者：

 #include <iostream>
 #include <time.h>
  using namespace std;
 
 timespec diff(timespec start, timespec end);
 
  int main()
 {
     timespec time1, time2;
     int temp;
     clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time1);
     for (int i = 0; i< 242000000; i++)
         temp+=temp;
     clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time2);
     cout<<diff(time1,time2).tv_sec<<":"<<diff(time1,time2).tv_nsec<<endl;
     return 0;
 }
 
 timespec diff(timespec start, timespec end)
 {
     timespec temp;
     if ((end.tv_nsec-start.tv_nsec)<0) {
         temp.tv_sec = end.tv_sec-start.tv_sec-1;
         temp.tv_nsec = 1000000000+end.tv_nsec-start.tv_nsec;
     } else {
         temp.tv_sec = end.tv_sec-start.tv_sec;
         temp.tv_nsec = end.tv_nsec-start.tv_nsec;
     }
     return temp;
 }

.c编译时需加上 -lrc