Yashavant Kanetkar Understanding Pointers in C, chapter 1, question number 1

Question

Can you write another expression which does the same job as  ++*ptr ?

Answer 1

In operator precedence list ++ and * have same priority. so we must go with associativity (Right to left).

lets take an example in an array A

value	4	6	9
address	100	200	300

at first  if we have ptr = A, it means address of first element of A i.e. 100 will be stored in ptr.

now ptr=100.

if we write *ptr , it means value of ptr i.e. 4

if we use ++ (pre-increment operator) as ++*ptr , value of 4 will be incremented by 1 and becomes 5.

which is same as writing *ptr = *ptr + 1.

i hope you got your answer.

Answer 2

++(*p) // first take the value and then  increment the value  //