这个函数指针变量怎么运行不了啊哪里出错了，请大家多多指教。谢谢啦！！
#include<stdio.h>int max(int a,int b){
if(a>b)return a;
else return b;
}
main(){
int max(int a,int b);
int(*pmax)();
int x,y,z;
pmax=max;
printf("input two numbers:\n");
scanf("%d%d",&x,&y);
z=(*pmax)(x,y);
printf("maxmum=%d",z);
