Memory Management Operator
In C malloc( ), calloc( ), realloc( ), and free( ) are used to mange dynamic memory. In
addition to these function C++ have derived two unary operators new and delete to perform dynamic allocation of memory. An object or variable may be created or destroyed by using these functions. The syntax for to create a dynamic memory allocation is
pointer_variable = new data_type;
p = new int;
The above two statements can be written in one stroke or line. int *p = new int;
*p = 25; Assigning 25 through pointer
It can also be initialized in one stroke or line. The syntax to initialize the new operator is:
pointer_variable = new data_type (value);
int *p = new int(25);
The new operator can also be used in array
int *pa = new int; This will create memory space for 10 integers the first element is
referred as p.....p;
When using multi dimension arrays all the array sizes must be specified, the first array may be variable the remaining must be constants.
pm = new int[N];
To release the memory the syntax is delete pointer_variable;
delete p; will release the memory stored by the pointer variable p. delete [ ]pa; will release dynamically allocated array.
The most widely used manipulators are endl and setw.
cout <<"This is C++ program"<< endl; The endl work just like "\n"
The setw operator is used to specify the width of the output. It is similar to %wd, %w.pf in C. The default is right justified
int x=10, y=1000;