y已经声明了，为什么仍然显示有错误？

Question

#include<stdio.h>
#include<stdlib.h>

gys(int u,int v);
gbs(int m,int n);
sxhs(); rnpd(int y);
sssy(int n);
jzxj(); yhsj();
sjpx(int a[]);
void main()
{
int y,i,m,u,v,s[10],gy,gb,n,k,sxh,jz,ss,yh;
以下省略

case 4:
printf("输入一个年份: ");
scanf("%d",&y);
rnpd(y);
break;

rnpd(y)
{int leap;
if(y%4==0)
{
if(y%100==0)
{
if(y%400==0)
leap=1;
else
leap=0;
} 
else
leap=1;
}
else
leap=0;
if(leap)
printf("is a leap year\n");
else
printf("is not a leap year\n");
}

y已经声明了，为什么电脑仍然说:546.cpp(144) : error C2065: 'y' : undeclared identifier

Answer 1

rnpd(int y) //这里忽略参数类型了。{int leap;if(y%4==0){if(y%100==0){if(y%400==0)leap=1;elseleap=0;}&nbsp;elseleap=1;}elseleap=0;if(leap)printf("is a leap year\n");elseprintf("is not a leap year\n");}

Answer 2

rnpd函数形参。。。void rnpd(int y){//...........}