er是一个大小为4个double的地址，为什么不符合形参double (*x)[4]？

Question

#include<stdio.h>
#include<conio.h>
void main(){
	double copy(double (*x)[4],double (*y)[4]);
	double er[4][4]={{1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}},er2[4][4];
	double copy (er,er2);
}
double copy(double (*x)[4],double (*y)[4]){
	for (int i = 0; i < 4; i++)
	{
		for (int k = 0; k < 4; k++)
		{
			*(*(y+i)+k)=*(*(x+i)+k);
		}
	}
}

Answer 1

第六行 去掉double ，直接用copy (er,er2);