c/c++ 数组 数组的引用，指针数组的引用

c/c++ 数组

知识点

1，数组的声明和初始化，对应代码里的test1和test2

2，char数组，对应代码里的test3

3，数组不可以拷贝和复制，对应代码里的test4

4，指针数组， 数组的指针， 数组的引用，指针数组的引用，对应代码里的test5

5，数组的范围for用法，对应代码里的test6

6，用size_t作为下标的类型，对应代码里的test6

#include <iostream>#include <string>#include <cstddef>using namespace std;int main(){  //test1 声明时必须指定数组的大小                                              
  /*                                                                            
  unsigned cnt = 42;                                                            
  constexpr unsigned sz = 42;                                                   
  int arr[10];                                                                  
  int *parr[sz];                                                                
  string bad[cnt];                                                              
  bad[23] = "aaa";                                                              
  cout << bad[23] << endl;                                                      
  */

  //test2 初始化                                                                
  /*                                                                            
  const unsigned sz = 3;                                                        
  int ia1[sz] = {1,2,3};//含有3个元素的数组，元素值：1,2,3                      
  int a2[] = {1,2,3};//含有3个元素的数组，元素值：1,2,3                         
  int a3[5] = {1,2,3};//含有5个元素的数组，元素值：1,2,3,0,0                    
  cout << a3[3] << a3[4] << endl;                                               
  string a4[3] = {"ni", "go"};//含有3个元素的数组，元素值："ni","go",""         
  cout << a4[2] << endl;                                                        
  //int a5[2] = {1,2,3};//错误                                                  
  */

  //test3 char数组                                                              
  /*                                                                            
  char a1[] = {'a','b','c'};//列表初始化，没有尾部\0                            
  cout << a1 << endl;//因为没有尾部的\0，所以会一直打印到\0为止                 
  char a2[] = {'a','b','c', '\0'};//列表初始化，有尾部\0                        
  cout << a2 << endl;                                                           
  char a3[] = "abc";//自动添加尾部的\0                                          
  cout << a3 << endl;                                                           
  //char a4[3] = "abc";//错误，指定了大小为3，无法在c后面加\0                   
  */

  //test4 数组拷贝和赋值                                                        
  /*                                                                            
  int a[] = {1,2,3};                                                            
  //int a1[] = a;//不能拷贝数组                                                 
  int a2[] = {1,1,1};                                                           
  //a2 = a;//不能用数组给数组赋值                                               
  */

  //test5 指针数组， 数组的指针， 数组的引用，指针数组的引用                    
  /*                                                                            
  //指针数组                                                                    
  int* pt[10];//ptr指向含有10个整型指针的数组                                   
  //数组的指针                                                                  
  int (*parr)[10];//parr指向一个含有10个整数的数组,应用于二维数组               
  int br[2][10];                                                                
  parr = br;                                                                    
  if(parr + 1 == &br[1]){                                                       
    cout << "==" << endl;                                                       
    parr[0][0] = 10;                                                            
    cout << br[0][0] << endl;                                                   
  }                                                                             
  int arr[10];                                                                  
  //数组的引用                                                                  
  int (&af)[2][10] = br;                                                        
  af[0][1] = 123;                                                               
  cout << br[0][1] << endl;                                                     
  int (&arrRef)[10] = arr;                                                      
  arrRef[0] = 100;                                                              
  arrRef[1] = 10;                                                               
  cout << arrRef[0] << "," << arrRef[1] << endl;                                
  //指针数组的引用                                                              
  int* (&ar)[10] = pt;                                                          
  int a = 5;                                                                    
  ar[0] = &a;                                                                   
  *ar[0] = 500;                                                                 
  cout << a << endl;                                                            
  */

  //test6 数组的范围for用法                                                     
  int ar[5] = {};  for(auto &s : ar){
    s = s + 1;
  }  //用size_t作为下标的类型，包括在cstddef头文件里                               
  size_t idx = 1;
  ar[idx] = 100;  for(auto s : ar){    cout << s << ",";
  }  cout << endl;
}

原文出处：https://www.cnblogs.com/xiaoshiwang/p/9625464.html