//running.c--一个对于长跑运动员有用的程序
#include <stdio.h>
const int S_PER_M = 60;            //第分钟的秒数
const int S_PER_H = 3600;        //第小时的秒数
const double M_PER_K 0.62137;    //第公里的英里数
int main (void)
{
    double distk, distm;        //分别以公里和英里计的跑过的距离
    double rate;                //以英里/小时为单位的平均速度
    int min, sec;                //跑步用时的分钟数和秒数
    int time;                    //用秒表示的跑步用时
    double mtime;                //跑完一英里所用的时间，以秒计
    int mmin, msec;                //跑完一英里所用的时间，以分钟和秒计
    printf ("This progam converts your time for metric race\n");
    printf ("to a time for running a mile and to your average\n");
    printf ("speed in miles per hour.\n");
    printf ("Please enter, in kilometers; the distance run.\n");
    scanf ("%lf", &distk);        //%lf表示读取一个double类型的数值
    printf ("Next enter the time in minutes and seconds.\n");
    printf ("Begin by entering the minutes.\n");
    scanf ("%d", &min);
    printf ("Now enter the seconds.\n");
    scanf ("%d", &sec);
//把时间转换为全部用秒表示
    time = S_PER_M * min + sec;
//把公里转换为英里
    distm = M_PER_K * distk;
//英里/秒 × 秒/小时 = 英里/小时
    rate = distm / time * S_PER_H;
//时间/距离 = 跑完第英里的用时
    mtime = (double)time / distm;
    mmin = (int)mtime / S_PER_H;    //求出分钟数
    msec = (int)mtime % S_PER_H;    //求出剩余的秒数
    printf ("You ran %l.2f km (%l.2f miles) in %d min. %d sec.\n",
        distk, distm, min, sec);
    printf ("That pace corresponds to running a mile in %d min.",
        mmin);
    printf ("%d sec.\nYour average speed was %l.2f mph.\n", msec,
        rate);
    return 0;
}

D:\Program Files\编程\编程EditPlus+GCC\EditPlus\Noname1.cpp:39: warning: unknown conversion type character `.' in format
D:\Program Files\编程\编程EditPlus+GCC\EditPlus\Noname1.cpp:39: warning: too many arguments for format
D:\Program Files\编程\编程EditPlus+GCC\EditPlus\Noname1.cpp:27: warning: unused variable 'M_PER_K'
编译失败！请检查错误！

晕啊，一发上来就发现了，少了个“=”号，晕死了，不好意思