int C(int x,int y) { int z; if((y==1)||(y=x+1))return 1; z=C(x-1,y-1)+C(x-1,y); return (z); }主函数调用这个函数,显示错误c was not declered in this scop.该怎么解决?

int C(int x,int y) { int z; if((y==1)||(y=x+1))return 1; z=C(x-1,y-1)+C(x-1,y); return (z); }主函数调用这个函数,显示错误c was not declered in this scop.该怎么解决?
int C(int x,int y) { int z; if((y==1)||(y=x+1))return 1; z=C(x-1,y-1)+C(x-1,y); return (z); }
主函数调用这个函数,显示错误c was not declered in this scop.该怎么解决?

int C(int x,int y) { int z; if((y==1)||(y=x+1))return 1; z=C(x-1,y-1)+C(x-1,y); return (z); }主函数调用这个函数,显示错误c was not declered in this scop.该怎么解决?
int C(int x,int y)
{
int z;
if((y==1)||(y=x+1))
return (1);
else
{
z=C(x-1,y-1)+C(x-1,y);
return (z);
}
}
话说函数声明了吗?