c++重载函数的简单运用

#include<iostream>
#include<cmath>
using namespace std;

int max1(int a , int b);
int max1(int a , int b ,int c);
double max1(double a , double b);
double max1(double a , double b ,double c);

int max1(int a , int b)
{
if(a>b)
return a;
else 
return b;
} 
int max1(int a , int b ,int c)
{
if(a > b && a>c)
return a;
else  if(b > a && b > c)
return b;
else
return c;   
} 
double max1(double a , double b)
{
if(a>b)
return a;
else
return b;
} 
double max1(double a , double b ,double c)
{
if(a > b && a>c)
return a;
else  if(b > a && b > c)
return b;
else
return c;   
} 
int main(){
int a, b , c;
cout<<"请输入三个整数：" ; 
cin>> a>> b>> c;
cout<<"请输入三个双精度数值：" ; 
double x, y ,z;
cin>>x >> y>>z;
cout<<max1(a,b)<<endl;
cout<<max1(a, b, c)<<endl;
cout<<max1(x , y)<<endl;
cout<<max1(x , y ,z)<<endl;
return 0;
}