#include <stdio.h>

int main(void)
{
    double yingchi=0;
    double ma,yingcun;
    printf("shu ru yingchi shi:");
    scanf("%lf",&yingchi);
    ma=yingchi*3;
    yingcun=yingchi/12;
    printf("ma:%lf,yingcun:%lf",ma,yingcun);
    return();
}

哦，知道了那去掉%lf中的l还是不行

哦，谢谢