Use of C ++ references

1 reference definition
C ++ is an important extension of C When referencing. The function of referencing is to give the variable an alias.

For example:

Int;

Int & B = a; // declare that B is a reference of

After the above statement, B becomes the alias of a. both a and B have the same status and role.

To declare B as a reference, you do not need to create new units for B. B and a occupy the same storage unit in the memory. They have the same address.

 

# Include <iostream> using namespace std; int main () {& nbsp; int a = 10; & nbsp; & nbsp; int & B = a; // declare that B is a reference & nbsp; cout <"B =" <B <endl; & nbsp; a = A-5; & nbsp; & nbsp; cout <"B =" <B <endl; & nbsp; B = B-1; & nbsp; cout <"a =" <a <endl; & nbsp; & nbsp; return 0 ;}

 

 

 

In the program,

Declares that B is a reference of a, and then outputs B = 10;

Then reduce the value of a by 5, and then output B = 5, which means that B will change with the change of;

Then reduce the value of B by 1, and then output a = 4, indicating that a will change with the change of B.

When declaring a reference, you must initialize it at the same time, that is, declare the variable that it represents. After declaring that variable B is a reference of variable a, you can use B as the alias of variable a, and B cannot be referenced as another variable (alias ).

Declare references without initialization:

 

 

#include<iostream>   using namespace std;  int main(){           int a=10;           int &b;                         return 0;  }  #include<iostream>using namespace std;int main(){         int a=10;         int &b;                       return 0;}