怎样求三个数的最大值？要是c语言的！

#include<stdio.h>
main()
{
int a,b,c;
scanf("%d,%d,%d",&a,&b,&c);
if((a>b)&&(a>c))
printf("the max is:%d",a);
else if((b>a)&&(b>c))
printf("the max is:%d",b);
else
printf("the max is:%d",c);

}

#include<stdio.h>
int max(int a,int b);
int min(int a,int b);
int main()
{
int a,b,c;
int he,pingjun,ji;
printf("please input three nunber:\n");
scanf("%d\n %d\n %d\n",&a,&b,&c);
he=a+b+c;
pingjun=he/3;
ji=a*b*c;
printf("he :%d\n",he);
printf("pingjun :%d\n",pingjun);
printf("ji :%d\n",ji);
printf("max :%d\n",max(a,max(b,c));
printf("min :%d\n",min(a,min(b,c));
return 0;
}
int max(int a,int b)
{
if(a>b) return a;
else return b;