/*
 * Copyright (c) JoinQuant Development Team
 * Author: Huayong Kuang <kuanghuayong@joinquant.com>
 *
 */

#include <iostream>

using namespace std;


void convert(int &a, int &b, bool a2b=true);


void addThree(int& num1, int& num2, int& num3, int& sum)
{
 sum = num1 + num2 + num3;
}

void convert(int &a, int &b, bool a2b) {
 if (a2b) {
 b = 1000;
 } else {
 a = 2000;
 }
}

void transfer_str(string &s1, const string &s2=string("111")) {
 s1 = s2;
}

int main(void)
{

	int n1 = 1, n2 = 2, n3 = 3, s;
	addThree(n1, n2, n3, s);
 cout << s << endl;

 int a;
 int b;
 int m = 10;
 convert(m, b);
 cout << b << endl;
 convert(a, m, false);
 cout << a << endl;

 string ss;
 transfer_str(ss);
 //transfer_str(ss, string("hello world"));
 cout << ss << endl;

 return 0;
}