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Questions tagged [post-increment]

For issues relating to defining or performing post increment operations.

Post-increment operators increase the value of their operand by 1 (or another specified amount), but the value of the operand in the expression is the operand's original value prior to the increment operation.

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What is the difference between ++i and i++?

In C, what is the difference between using ++i and i++, and which should be used in the incrementation block of a for loop?
The.Anti.9
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Is there a performance difference between i++ and ++i in C?

Is there a performance difference between i++ and ++i if the resulting value is not used?
Mark Harrison
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Is there a performance difference between i++ and ++i in C++?

We have the question is there a performance difference between i++ and ++i in C? What's the answer for C++?
Mark Harrison
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Difference between pre-increment and post-increment in a loop?

Is there a difference in ++i and i++ in a for loop? Is it simply a syntax thing?
GurdeepS
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What is x after "x = x++"?

What happens (behind the curtains) when this is executed? int x = 7; x = x++; That is, when a variable is post incremented and assigned to itself in one statement? I compiled and executed this. x is still 7 even after the entire statement. In my…
Michael
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How do the post increment (i++) and pre increment (++i) operators work in Java?

Can you explain to me the output of this Java code? int a=5,i; i=++a + ++a + a++; i=a++ + ++a + ++a; a=++a + ++a + a++; System.out.println(a); System.out.println(i); The output is 20 in both cases
Ankit Sachan
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Difference between *ptr += 1 and *ptr++ in C

I just started to study C, and when doing one example about passing pointer to pointer as a function's parameter, I found a problem. This is my sample code : #include #include #include int* allocateIntArray(int*…
huy nguyen
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Incrementing in C++ - When to use x++ or ++x?

I'm currently learning C++ and I've learned about the incrementation a while ago. I know that you can use "++x" to make the incrementation before and "x++" to do it after. Still, I really don't know when to use either of the two... I've never really…
Jesse Emond
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The difference between ++Var and Var++

In programming, particularly in Java, what is the difference between: int var = 0; var++; and int var = 0; ++var; What repercussions would this have on a for loop? e.g. for (int i = 0; i < 10; i++) {} for (int i = 0; i < 10; ++i) {}
user559142
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increment value of int being pointed to by pointer

I have an int pointer (i.e., int *count) that I want to increment the integer being pointed at by using the ++ operator. I thought I would call: *count++; However, I am getting a build warning "expression result unused". I can: call *count +=…
joels
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Post-increment and Pre-increment concept?

I don't understand the concept of postfix and prefix increment or decrement. Can anyone give a better explanation?
Saad Masood
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Pre- & Post Increment in C#

I am a little confused about how the C# compiler handles pre- and post increments and decrements. When I code the following: int x = 4; x = x++ + ++x; x will have the value 10 afterwards. I think this is because the pre-increment sets x to 5, which…
Schweder
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Why is "while (i++ < n) {}" significantly slower than "while (++i < n) {}"

Apparently on my Windows 8 laptop with HotSpot JDK 1.7.0_45 (with all compiler/VM options set to default), the below loop final int n = Integer.MAX_VALUE; int i = 0; while (++i < n) { } is at least 2 orders of magnitude faster (~10 ms vs. ~5000 ms)…
sikan
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++i or i++ in for loops ??

Possible Duplicate: Is there a performance difference between i++ and ++i in C++? Is there a reason some programmers write ++i in a normal for loop instead of writing i++?
Ismail Marmoush
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Why doesn't the post increment operator work on a method that returns an int?

public void increment(){ int zero = 0; int oneA = zero++; // Compiles int oneB = 0++; // Doesn't compile int oneC = getInt()++; // Doesn't compile } private int getInt(){ return 0; } They are all int's, why won't B & C…
Blundell
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