A double pointer has two basic meanings. One is ofa pointer to a pointer, where changing the value ofdouble pointer will result in the original pointer being changed. Another is that of a two-dimentional array, such as a matrix, or a list of char* (e.g. in main when you use argv).
insert or delete values both side.so use double pointer
Double pointer is a pointer to a pointer. So you can work with the double pointer as you work with a single one.Or you might mean 'pointer to double', eg:void clear_double (double *dp){*dp = 0;}
Double (**) is used to denote the double pointer. As we know the pointer stores the address of variable, Double pointer stores the address of any pointer variable. Declaration : int **ptr2Ptr;
Buttons and pointer options
The double star (**) notation is not specific to initializing a variable in a class. It is simply a double indirect reference to an object.float myFloat; // an objectfloat *myFloatPtr; // a pointer to an objectfloat **myFloatPtrPtr; // a pointer to a pointer to an objectmyFloat = 123.456; // initialize an objectmyFloatPtr = &myFloat; // initialize a pointer to an objectmyFloatPtrPtr = myFloatPtr; // initialize a pointer to a pointer to an objectmyFloat; // refer to an object*myFloatPtr; // refer to an object through a pointer**myFloatPtrPtr; // refer to an object through a pointer to a pointer*myFloatPtrPtr; // refer to the value of the pointer to the objectDouble pointer notation is used where the caller intends that one of its own pointers need to be modified by a function call, so the address of the pointer, instead of the address of the object, is passed to the function.An example might be the use of a linked list. The caller maintains a pointer to the first node. The caller invokes functions to search, add, and remove. If those operations involve adding or deleting the first node, then the caller's pointer has to change, not the .next pointer in any of the nodes, and you need the address of the pointer to do that.
The shape attached to the pointer
example: double num = 12.34; double *numptr = # double **numptrptr = &numptr;
because u freakin can
Pointer to Pointer is a double pointer, denoted by (**). Pointer stores the address of the variable and pointer to pointer stores the address of a pointer variable and syntax can be given as int **ptr2ptr;
yea that's why its called the point FINGER
No, 'void *' and 'double *' are ok; 'void double *' is syntax error.On the other hand 'void **p' is totally correct: p holds the address of a generic pointer.
Pointer is a variable that stores the address of another variable. Since pointer is also akind of variable, thus pointer itself will be stored at a different memory location.