#include <iostream> 
 
using namespace std ;  
 
void say_hello(void) 
{ 
  cout << "this is hello" << endl ;  
} 
  
 
//数据类型不同的重载 
void say_hello(int a = 100) 
{ 
  cout << "this is hotdog" << endl ;  
} 
 
int say_hello(double a ) 
{ 
  cout << "this is hotpig:" << a << endl ;  
} 
//参数个数不同的重载 
int say_hello(int a, int b, int c) 
{ 
  cout << "a+b+c = " << a+b+c << endl ;  
}  
 
int main(void) 
{ 
  say_hello(100); 
  say_hello(11.11); 
  say_hello(1 , 2 , 3); 
  return 0 ; 
}</span> 

this is hotdog 

this is hotpig:11.11 

a+b+c = 6