Pointer vs Array in C (original) (raw)

Last Updated : 23 Jul, 2025

Most of the time, pointer and array accesses can be treated as acting the same, the major exceptions being:

1. the sizeof operator

• sizeof(array) returns the amount of memory used by all elements in the array
• sizeof(pointer) only returns the amount of memory used by the pointer variable itself

2. the & operator

• array is an alias for &array[0] and returns the address of the first element in the array
• &pointer returns the address of the pointer

3. a string literal initialization of a character array

• char array[] = “abc” sets the first four elements in array to ‘a’, ‘b’, ‘c’, and ‘\0’
• char *pointer = “abc” sets the pointer to the address of the “abc” string (which may be stored in read-only memory and thus unchangeable)

4. Pointer variable can be assigned a value whereas an array variable cannot be.

int a[10]; int *p; p=a; /legal/ a=p; /illegal/

5. Arithmetic on pointer variable is allowed.

p++; /Legal/ a++; /illegal/

6. Array is a collection of similar data types while the pointer variable stores the address of another variable.

Please refer Difference between pointer and array for more details.