计算x的y次方的值

#include<stdio.h>
double fun(int x,int y)
{
  int i=1;
  double z=1;

  for(i=1;i<=y;i++)
     z=z*x;

  return z;

}

int main()
{
  double fun(int x,int y);
  double z;
  int x,y;
  
  printf("please input x y:");
  scanf("%d %d",&x,&y);
  
  z=fun(x,y);

  printf("z=%.1f\n",z);

  return 0;

}