What are the advantage of pointers in c?

Answer 1

Pointers are addresses to locations in memory which store data.

Under normal circumstances, memory for variables is already allocated when the program runs. The size of the memory cannot be changed, which is insufficient for some applications.

Hence, memory allocation, reallocation and deallocation functions exist to allow the programmer more freedom in using memory.

Blocks of memory allocated by the program can be easily resized or reallocated for other purposes. For instance, an array declared as follows:

int myarray[20];

has, and will always have, 20 values - it cannot resize, and is known as a static array. However, if you want to be able to resize this array, it's best to redeclare it as an intpointer:

int *myarray=NULL;

Thus, realloc() is the only function necessary for manipulating it:

myarray=(int*)realloc(myarray, sizeof(int)*newarraysize);

Set the new value for newarraysize, and make the above call to resize the array. Then, when you're done with myarray, free(myarray). This is called a dynamic array, since it can be resized dynamically.

Another use of pointers is in linked lists, which are valuable when inserting or removing items to or from arbitrary locations in a list is desired. Allocate the memory for a new node, adjust the variables pointing to the old node to the new node, and free the memory for the old node. Linked lists are faster than arrays in this case, particularly when dealing with large amounts of data.

Answer 2

The pointer indicates the location of variable . and also *p is indicates the value of the corresponding pointer address....... this is basic advantage of pointers...