求大侠帮忙填一下这两道c++题，小弟刚学一头雾水，谢谢了！

Question

1.求出圆柱的表面积和体积:
#include <iostream.h>
class circle
{
public:
circle(float r)
{ ____R=r___________ }
float area()
{ return 3.14*R*R; }
float get_R() {return R;}
private:
float R;
};

class column:public circle
{
public:
column(float r,float h): ___circle(r)____________
{ }
float area()
{
float s;
s= circle::area()*2+2*3.14*circle::get_R();
return s;
}
float volume()
{ return ___s*h____________; }
private:
float H;
};
void main()
{
circle circle1(10);
cout<<"半径为10的圆的面积="<<circle1.area ()<<endl;
column column1(20,30);
cout<<"半径为20高为30的圆柱的表面积="<<column1.area ()<<endl;
cout<<"半径为20高为30的圆柱的体积="<<column1.volume()<<endl;
}
2、找出两个整数的最大公约数
#include "iostream.h"
int max(int x,int y)
{
int i;
for(i=_______________;i>=1;i--)
if(x%i==0&&y%i==0)
break;
_______________;
}
main()
{
int m,n;
cin>>m>>n;
cout<<max(m,n)<<endl;
}

Answer 1

这事第二个：
#include "iostream.h"
int max(int x,int y)
{
int i;
for(i=x;i>=1;i--)
if(x%i==0&&y%i==0)
break;
return i;
}
main()
{
int m,n;
cin>>m>>n;
cout<<max(m,n)<<endl;
}

Answer 2

{ ____R=r___________ } ==》R = r;
return ___s*h____________; } return circle::area()*H;

for(i=_______________;i>=1;i--) ==>for(i = x>y?y:x;...)

_______________;==>return i;