005_linuxC++之_指针的引入

 1 #include <iostream>
 2 using namespace std;
 3 int add(int a){
 4     a = a + 1;
 5     return a;
 6 }
 7 int add(int *a){
 8     *a = *a + 1;
 9     return *a;
10 }
11 int add_ref(int &b){
12     b = b + 1;
13     return b;
14 }
15 int main(int arg,char ** argv){
16     int a = 99;
17     int &c = a;                /*使用符号&来进行引用，引用之后c++就相当于a地址中的数进行a++*/
18     cout<<add(a)<<endl;        /*传入的是参数*/  /*a = 99*/
19     cout<<"a = "<<a<<endl;                      /*a = 99*/
20     
21     cout<<add(&a)<<endl;    /*传入的地址*/    /*a = 100*/
22     cout<<"a = "<<a<<endl;                      /*a = 100*/
23 
24     cout<<add_ref(a)<<endl;    /*引用*/          /*a = 101*/
25     cout<<"a = "<<a<<endl;                      /*a = 101*/
26     
27     c++;                                      /*a = 102*/
28     cout<<"a = "<<a<<endl;                      /*a = 102*/
29     cout<<"c = "<<c<<endl;                      /*a = 102*/
30     return 0;
31 }