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Questions tagged [pre-increment]

For issues relating to defining or performing pre increment operations.

Pre-increment operators increase the value of their operand by 1 (or another specified amount), and the value of the operand in the expression is the operand's value after 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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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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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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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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Preincrement faster than postincrement in C++ - true? If yes, why is it?

I heard about that preincrements (++i) are a bit faster than postincrements (i++) in C++. Is that true? And what is the reason for this?
user163408
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Expressions "j = ++(i | i); and j = ++(i & i); should be a lvalue error?

I was expecting that in my following code: #include int main(){ int i = 10; int j = 10; j = ++(i | i); printf("%d %d\n", j, i); j = ++(i & i); printf("%d %d\n", j, i); return 1; } expressions j = ++(i |…
Grijesh Chauhan
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Post-increment within a self-assignment

I understand the differences between i++ and ++i, but I'm not quite sure why I'm getting the results below: static void Main(string[] args) { int c = 42; c = c++; Console.WriteLine(c); //Output: 42 } In the above code, as this is…
Siyual
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Java: Prefix/postfix of increment/decrement operators

From the program below or here, why does the last call to System.out.println(i) print the value 7? class PrePostDemo { public static void main(String[] args) { int i = 3; i++; System.out.println(i); // "4" …
O_O
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