C语言程序设计源代码：C67求两数乘积

#include<stdio.h>
float mul(float a,float b);
main()
{
float x,y,z;
printf(“请输入两个数：”);
scanf("%f %f",&x,&y);
z=mul(x,y); /*①*/
printf(“mul(%f,%f)=%f,”,x,y,z);
x=x+10; /*对x和y进行变换*/
y=y-10;
mul(x,y); /*②*/
x=x*2; /*再次对x和y进行变换*/
y=y*2;
printf("mul(%f,%f)=%f\n",x,y,mul(x,y)); /*③*/
}
float mul(float a,float b)
{
return a*b;
}