程序代码：

#include<stdio.h>
#include<math.h>

main()
{
    double a=0.0;
    int b;
    double c;
  
    printf("This project is used to separate the integer and decimal part of a  number\n");
    printf("please input the number:\n");
    scanf("%lf",&a);

    if (a>=0.0)
        {
            b=(int)floor(a);
            printf("the integer of the number you input is %d\n",b);
        }
    else if(a<0.0)
        {
            b=(int)ceil(a);
            printf("the integer of the number you input is %d\n",b);
        }
    else
        printf("Please check the number you input");

    c=a-b;
    printf("the decimal part of the number you input is %g\n",c);

    return 0;
}