请教c++的高手们一个简单的问题

谢谢了
还有一个问题
定义一个类保存为1.h
#ifdef MONEY_H
#define MONEY_H
class Money
{
    public:
    Money();
    Money(long doller,int cent);
    Money(double amout);
    void assignMoney(long doller,int cent);
    void assignMoney(double amount);
    void addTo(Money cash);
    void muitiplyBy(double num);
    double quot(Money cash);
    bool lessthan(Money cash),equalto(Money cash);    
    void display();
    private:
    long dollerandcent;
    long round(double num);
    
};
#endif
能否被2.h引用
#include <iostream>
using namespace std;
#include "1.h"
void Money::Money()
{
    dollerandcent=0;
}
void Money::Money(long doller,int cent)
{dollerandcent=doller*100+cent;
}
void Money::Money(double amount)
{ dollerandcent=round(amount*100);
}

void Money:: assignMoney(long doller,int cent)
{dollerandcent=doller*100+cent;
}

void Money::assignMoney(double amount)
{ dollerandcent=round(amount*100);
}
void Money::addTo(Money cash)
{dollerandcent=dollerandcent+cash.dollerandcent;
    }
void Money::muitiplyBy(double num)
{dollerandcent=round(amount*100);
}
double Money::quot(Money cash){
return static_cast<double>(dollerandcent)/cash.dollerandcent;
}
bool Money::lessthan(Money cash)
{bool ret;
    if(dollerandcent<cash.dollerandcent)
    ret=true;
    else
    ret=false;
    return ret;
}
bool Money::equalto(Money cash)
{bool ret;
    if(dollerandcent==cash.dollerandcent)
    ret=true;
    else
    ret=false;
    return ret;
}
void Money::display()
{int cent;
    cout<<dollerandcent/100<<".";
    cent=dollerandcent%100;
    if (cent<10)
    cout<<"0";
    cout<<cent;
}
long Money::round(double num)
{long ron;
    if (num>=0)
    ron=static_cast<long>(num+0.5);
    else
    ron=static_cast<long>(num-0.5);
    return ron;
}
也就是把函数声明和函数定义放在两个文件中。可以吗

#ifdef MONEY_H
#define MONEY_H

明显有错误