Prefix and postfix operators necessity

Question

What is the necessity of both prefix and postfix increment operators? Is not one enough?

To the point, there exists like a similar while/do-while necessity problem, yet, there is not so much confusion (in understanding and usage) in having them both. But with having both prefix and postfix (like priority of these operators, their association, usage, working). And do anyone been through a situation where you said "Hey, I am going to use postfix increment. Its useful here."

Answer 1

POSTFIX and PREFIX are not the same. POSTFIX increments/decrements only after the current statement/instruction is over. Whereas PREFIX increments/decrements and then executes the current step. Example, To run a loop n times,

while(n--)
{ }

works perfectly. But,

while(--n)
{
}

will run only n-1 times

Or for example:

x = n--; different then x = --n; (in second form value of x and n will be same). Off-course we can do same thing with binary operator - in multiple steps.

Point is suppose if there is only post -- then we have to write x = --n in two steps.

_{There can be other better reasons, But this is one I suppose a benefit to keep both prefix and postfix operator.}