c语言多参数函数写法

#include"stdio.h"
////多参数////////////////

long sum(int i,...)
{
int *p,j;
long s = 0;
p = &i+1;
for (j=0;j<i;j++)
   s += p[j];
    return s;
}
void main()
{
long Sum = sum(3,1,2,3);
printf("%ld",Sum);
//Sum == 6;
}