问一个问题

# include <stdio.h>
void main ()
{
int max（int x, int y）;
int a, b, c;
scanf (" %d, %d", &a, &b);
c = max (a, b);
printf ("max = %d\n",c);
}
int max (int x,int y)
{
int z;
if (x > y) z = x;
else z = y;
return (z);
}