#include <iostream>
using namespace std;
void test01()
{
	int a = 10;
	int& b = a;
	b = 100;
	cout << a << endl;
 
	int c = 1;
	//b = c; 代表把c的值賦值給b 不是給c取別名為b
	//int &d; 引用定義時必須初始化
}
 void test02()
 {
	int a[5] = { 1,2,3,4,5 };//int(&arr)[5] = a;
	 typedef int ARR[5];  //type & 別名 = 舊名
	 ARR & arr = a;
	 for (int i = 0; i < 5; i++)
	 {
		 cout << arr[i] << " ";
		
	  }
	 cout << endl;
	
 }
 int main()
{
	 test02();
	
	 return 0;
}

swap(int *x ,int *y)
{
	int temp = *x;
	*x = *y;
	*y = temp;
}
 
void test01()
{
	int a = 10;
	int b = 20;
	swap(&a,&b);
 
} 

void swap_ref(int &x, int &y)// int &x =a, int &y =b
 {
   int tmp = x;
   x = y;
   y = tmp;
 
 }
 void test01_ref()
 {
   int a = 10; 
   int b = 20;
   swap_ref(a, b);
 }

//形參是指針 引用
void get_mem(int **q)
{
  *q = (int *)malloc(5 * sizeof(int));
}
void test03()
{
  int *p = NULL;
  get_mem(&p);
  get_mem_ref(p);
}

void get_mem_ref(int * &q)//int * (&q) = p
{
    q = (int *)malloc(5 * sizeof(int));
 
}
void test03()
{
  int *p = NULL;
  get_mem(&p);
  get_mem_ref(p);
}

int & test04()
{
   //能不能返回一個變量的引用 看這個變量的空間是否被釋放了
   static int b = 100;
   int a = 10;
   //return a;//err 不能返回局部變量的引用
   return b;//可以返回靜態(tài)的變量的引用
 
 }

void test03()
{
? int *p = NULL;
? get_mem(&p);
? get_mem_ref(p);
}

int a = 10; 
 
const int &b = a;

int &b = 100; //不能引用常量

const int &b = 1;

int tmp =1 ,const int &b= tmp;