程序代码：

#include <stdio.h>
#include <math.h>
void main()
{
    double a,b,c;
       
        printf("please input first number:");
        scanf("%f",&a);
        printf("please input second number:");
        scanf("%f",&b);
          c=a+b;
            printf("the mum is: %f \n,&c");
            return 0;
}