内联函数&重载函数&函数参数缺省值

内联函数

#include<bits/stdc++.h>
using namespace std;
inline int Max(int,int);
int main(void)
{
    int a,b,c,d,e,f;
    scanf("%d %d %d %d %d %d",&a,&b,&c,&d,&e,&f);//1 2 3 4 5 6
    int k=Max(a,b);
    //编译器会将这句指令编译成如下
    /*if(a>b){
        tmp=a
    }else{
        tmp=b;
    }
    k=tmp;*/
    int m=Max(c,d);
    int n=Max(e,f);
    cout<<k<<endl;//2
    cout<<m<<endl;//4
    cout<<n<<endl;//6
    return 0;
}
inline int Max(int x,int y)
{
    return x>y?x:y;
}

重载函数

#include<bits/stdc++.h>
using namespace std;
double Max(double,double);
int Max(int,int);
int main(void)
{
    double a,b;
    int c,d;
    scanf("%lf %lf %d %d",&a,&b,&c,&d);//3.5 2.4 3 6
    double k=Max(a,b);//Correct
    int m=Max(c,d);//Correct
    int n=Max(a,c);//Error:call of overloaded 'Max(double&, int&)' is ambiguous
    cout<<k<<endl;//3.5
    cout<<m<<endl;//6
    return 0;
}
double Max(double m,double n)
{
    return m>n?m:n;
}
int Max(int x,int y)
{
    return x>y?x:y;
}

函数的缺省参数