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How to initialize array to 0 in C?
I need a big null array in C as a global. Is there any way to do this besides typing out
2 Answers
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List comprehension in Ruby
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If you really want to, you can create an Array#comprehend method like this:
class Array
def comprehend(&block)
return self if block.nil?
self.collect(&block).compact
end
end
some_array = [1, 2, 3, 4, 5, 6]
new_array = some_array.comprehend {|x|...
How to check if array element exists or not in javascript?
...
Use typeof arrayName[index] === 'undefined'
i.e.
if(typeof arrayName[index] === 'undefined') {
// does not exist
}
else {
// does exist
}
share
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Do I have to guard against SQL injection if I used a dropdown?
...mple to make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be,...
Is arr.__len__() the preferred way to get the length of an array in Python?
...tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public .length()...
java: ArrayList - how can i check if an index exists?
I'm using ArrayList<String> and I add data at specific indices,
how can I check if a specific index exists?
11 Ans...
How to make an array of arrays in Java
Hypothetically, I have 5 string array objects:
4 Answers
4
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What is an IndexOutOfRangeException / ArgumentOutOfRangeException and how do I fix it?
... equal to the number of elements it contains.
When It Is Thrown
Given an array declared as:
byte[] array = new byte[4];
You can access this array from 0 to 3, values outside this range will cause IndexOutOfRangeException to be thrown. Remember this when you create and access an array.
Array L...
delete vs delete[] operators in C++
...w.
The delete [] operator deallocates memory and calls destructors for an array of objects created with new [].
Using delete on a pointer returned by new [] or delete [] on a pointer returned by new results in undefined behavior.
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What is a monad?
...unctions (that is, functions which can take other functions as arguments).
Arrays in JavaScript support the pattern, so let’s use that as the first example.
The gist of the pattern is we have a type (Array in this case) which has a method which takes a function as argument. The operation supplied ...