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What is the difference between float and double?
I've read about the difference between double precision and single precision. However, in most cases, float and double seem to be interchangeable, i.e. using one or the other does not seem to affect the results. Is this really the case? When are floats and doubles interchangeable? What are the d...
What do numbers using 0x notation mean?
... @Luc The first one is correct. Although more often I see just 0xffffffff and such. (0xffffffff = -1 for 32-bit int assuming 2's complement)
– Mysticial
Jul 23 '13 at 16:30
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Check if a string is html or not
...se. If you use a < b && a > c the browser will turn the > and < characters into &gt; and &lt; entities appropriately. If, instead, you use a<b && a>c the browser will interpret the markup as a<b && a>c</b> because the lack of a space mean...
Foreign Key to multiple tables
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You have a few options, all varying in "correctness" and ease of use. As always, the right design depends on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table.
You could create M:M referen...
Redefining NULL
I'm writing C code for a system where address 0x0000 is valid and contains port I/O. Therefore, any possible bugs that access a NULL pointer will remain undetected and at the same time cause dangerous behaviour.
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Setting variable to NULL after free
...dangling pointer is accessed after it is freed, you may read or overwrite random memory. If a null pointer is accessed, you get an immediate crash on most systems, telling you right away what the error is.
For local variables, it may be a little bit pointless if it is "obvious" that the pointer isn...
What does the caret operator (^) in Python do?
I ran across the caret operator in python today and trying it out, I got the following output:
5 Answers
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MVC pattern on Android
...it possible to implement the model–view–controller pattern in Java for Android?
21 Answers
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What is meant by 'first class object'?
...them
in data structures, passing them as
arguments to other functions, and
returning them as the values of other
functions.
This page also illustrates it beautifully:
Really, just like any other variable
A function is an instance of the Object type
A function can have properties and...
What is the difference between a reference type and value type in c#?
Some guy asked me this question couple of months ago and I couldn't explain it in detail. What is the difference between a reference type and a value type in C#?
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