函数重载-C++

/*
功能：函数重载
日期：2013-09-23
*/
#include <iostream>
using namespace std;

int fun(int a=1,int b=2)
{
	int sum;

	sum = a * a + b * b;

	return sum;
}
float fun(float a,float b)
{
	float sum;

	sum = a * a + b * b;

	return sum;
}
double fun(double a,double b)
{
	double sum;

	sum = a * a + b * b;

	return sum;
}
int main(void)
{

	cout<<"fun():"<<fun()<<endl;
	cout<<"fun(2.5f,3.3f):"<<fun(2.5f,3.3f)<<endl;
	cout<<"fun(1.5,1.2):"<<fun(1.5,1.2)<<endl;

	system("pause");
	return 0;
}