linux c获取程序运行时间

#include <stdio.h>
#include <time.h>

int main() {
    clock_t start, end;
    double cpu_time_used;

    start = clock();

    // 这里放置需要测量时间的代码
    for (int i = 0; i < 1000000; i++) {
        // 模拟工作负载
    }

    end = clock();
    cpu_time_used = ((double) (end - start)) / CLOCKS_PER_SEC;

    printf("程序运行时间: %f 秒\n", cpu_time_used);
    return 0;
}

#include <stdio.h>
#include <sys/time.h>

int main() {
    struct timeval start, end;
    long seconds, useconds;
    double mtime;

    gettimeofday(&start, NULL);

    // 这里放置需要测量时间的代码
    for (int i = 0; i < 1000000; i++) {
        // 模拟工作负载
    }

    gettimeofday(&end, NULL);

    seconds = end.tv_sec - start.tv_sec;
    useconds = end.tv_usec - start.tv_usec;

    mtime = ((seconds) * 1000 + useconds/1000.0) + 0.5;

    printf("程序运行时间: %f 毫秒\n", mtime);
    return 0;
}