问一个低级的inline问题：

[nj_liuzl]

#include <iostream>
using namespace std;
class rational{
public:
       rational(int n = 0):a(0), q(1){}
       rational(int i, int j):a(i),q(j){}
       rational(double r):a(static_cast<long>(r*BIG)),q(BIG){}
       void print()const{
           cout << a << "/" << q;
       }
       operator double(){
           return static_cast<double>(a) / q;
       }
private:
        long a, q;
        enum {BIG = 100};
};

inline int greater(int i , int j){
    return i > j ? i:j;
}

double greater(double x, double y){
    return x > y ? x:y;
}

rational greater(rational w, rational z){
       return w>z?w:z;
}

int main(){
    int i  = 10, j = 5;
    float x = 7.0;
    
    double y = 14.5;
    
    rational w(10), z(3.5), zmax;

    cout << "\ngreater(" << i << "," << j << ")=" << greater(i,j);
    
}

这段代码，为什么编译的时候会出现：
`greater' undeclared (first use this function)
(Each undeclared identifier is reported only once for each function it appears in.)

错误啊~~

[Csuxiaowu]

rational greater(rational w, rational z){
return w>z?w:z;
}

[十八道胡同]

你的greater和std里面的greater冲突了，你要改你的函数的名字

[十八道胡同]

#include <iostream>
using namespace std;
class rational{
public:
       rational(int n = 0):a(0), q(1){}
       rational(int i, int j):a(i),q(j){}
       rational(double r):a(static_cast<long>(r*BIG)),q(BIG){}
       void print()const{
           cout << a << "/" << q;
       }
       operator double(){
           return static_cast<double>(a) / q;
       }
private:
        long a, q;
        enum {BIG = 100};
};

inline int great(int i , int j){
    return i > j ? i:j;
}

double great(double x, double y){
    return x > y ? x:y;
}

rational great(rational w, rational z){
       return w>z?w:z;
}

int main(){
    int i  = 10, j = 5;
    float x = 7.0;

    double y = 14.5;

    rational w(10), z(3.5), zmax;

    cout << "\ngreater(" << i << "," << j << ")="
    << great(i , j);

}

[delphiwcdj]

直接放在class里面

[pengzhixi]

改名字就可以了。