Why we use increment or decrement operator

Hi. I want to know that is there any advantage of using the increment or the decrement operator. Does it makes the code a bit faster to run, etc.
Actually i find these operators to be a bit confusing. so want to ask why should we use them and when.
Thanks.

baftos wrote:
I am not kidding. It's a personal opinion that may be wrong.
I'll tell you why I think what I think and I would be glad to change my opinion if someone shows me the light.
Those operators are just syntactic sugar.So is a bunch of other stuff in Java (imports and the foreach loop, for example). Syntactic sugar is a good thing when it makes common idioms more compact, or stand out as what they are, as opposed to just another instance of a more general case. (Although I don't really consider these syntactic sugar.)
Everything they do can be done otherwise more clearly.I disagree. "Increment" is an all-pervasive operation in programming. Sure, it can be done as just another case of x = x + something, where in this case something happens to be one, but in my opinion, that's not as descriptive. x++ is compact, concise, easy to read, and stands out clearly as "increment x".
Without them the language would be just simpler.
No more riddles about i=i++, Any language feature can be abused or misunderstood. That in itself is not a valid argument against including it. This misunderstanding is very easy to correct. It's on the same scale with redeclaring a member as a local and then wondering why you're getting NPE when trying to use the member elsewhere. It's not even in the same league as things like operator overloading or MI of implementation.
why n=i+1 requires cast, but not n=++i, the relation between boxing and the ternary etc.Again, these are little quirks, corner cases that cause some minor confusion but not major problems. To me this kind of stuff is no different than stuff like using compile-time constants for case conditions or to assign a wider integer type to a narrow one without a cast. It's stuff that makes the language easier to read and write for a lot of common use cases, at the cost of some minor complexity in the corners.
They were retained from C, while other things were discardedWhich is neither an argument for nor against them.
Edited by: jverd on Oct 31, 2009 9:37 AM

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jverd wrote:
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Hi Harish,
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adddbxxxx
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Decrement operator precedence confusion

Here is the snippet from a book:
int y = 5;
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System.out.println("result = " + result);Assuming increment and decrement have highest precedence, I don't get the explanation:
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resulting in 15 / 3 , which is 5. The output of this code is:
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AntShay wrote:
Oh, no!
There's something more I don't get :)
Why is 5 *** 3 takes place instead of 4 *** 3? Pre-decrement has higher precedence, hasn't it?
So, from my point of view this should work as follow (please correct me where I'm wrong):
int y = 5;
int result = y-- *** 3 / --y;
1) y-- gets evaluated (y=4 now)
2) --y gets evaluated (y=3)
3) 3 *** 3 = 9
4) 9/3 = 3I don't know if pre-dec has higher precedence than mult, but even if it does, that doesn't matter. That's not what precedence means. It doesn't mean you jump around and do those operations first. I just means "This is where the implied parentheses go." The only affect it has on order of evaluation is when you have to evaluate something inside the implied parens first to get an operand for the next operation.
3 + 4 * 5In the above, mult has higher precedence than add, so it's equivalent to
3 + (4 * 5)It doesn't mean "first do all multiplications, then all adds." It means the implied parens are as above.
So:
1. evaluate 3
2. evaluate the RH operand of +++
2.1 evaluate 4
2.2 valuate 5
2.3 multiply 4 *** 5 --> 20
3. evaluate 3 +++ 20
So we did the mult before the add because we had to in order to get the value of the RHS operand of the plus. Indirectly it's because mult has higher precedence, but that's just a consequence of the implied parens, and we still evaluated the 3 before doing the mult. We did NOT do "all mults first, then all adds."
Similarly, if it had been
2 + 3 + 4 * 5we would eval 2, then eval 3, then add, then eval the RHS of the second plus operator, which means we'd have to eval 4 *** 5. Note that we do NOT eval 4 *** 5 as the very first step before all adds.
Now, say pre-dec has higher precedence than mult. It may, it may not, I don't know and I don't care. It doesn't matter here, but let's say it does.
y-- * 3 / --yis the same as
(y--) * 3 / (--y)Operands are still evaluated L to R. We don't just jump around.
1. Evaluate y--
1.1 value of expression is 5
1.2 decrement y to 4
2. Evaluate 3.
3. Multiply #1 *** #2 --> 5 *** 3 = 15
4. Evaluate --y
4.1 decrement y
4.2 valueof expression is 3
5. evaluate #3 / #4 --> 15 / 3 = 5
Edited by: jverd on Feb 12, 2010 11:54 AM
Edited by: jverd on Feb 12, 2010 11:56 AM

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Hi all !
Even if i do understand how ++ and -- operators works fine (as a pre-modifers and post-modifers) but i can't understand how do they got the HIGHTEST precedence (unary operators) over than other operators , consider the follwing examples :
Ex(1):
======
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i know the process goes like this :
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======
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Q(1) is : why do assignment first then increment even
if operator ++ has higher precendence than "="
operator.
(i understand that that is true if y=++x, but why? ).The assignment is not performed first:
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Why we use increment or decrement operator

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