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parseInt vs unary plus, when to use which?
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The unary + on the other hand will return NaN if the entire string is non-convertible to a number.
parseInt('2a',10) === 2; //true
parseFloat('2a') === 2; //true
isNaN(+'2a'); //true
As seen in the comment of @Alex K., parseInt and parseFloat will parse by character. This means ...
C++ sorting and keeping track of indexes
...alues) : _values(values) {} public: bool operator() (const int& a, const int& b) const { return (_values)[a] > (_values)[b]; } };
– Yoav
Oct 18 '12 at 7:47
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How to display long messages in logcat
...u want to log with String.subString() and log it in pieces. For example:
int maxLogSize = 1000;
for(int i = 0; i <= veryLongString.length() / maxLogSize; i++) {
int start = i * maxLogSize;
int end = (i+1) * maxLogSize;
end = end > veryLongString.length() ? veryLongString.length()...
How to iterate through SparseArray?
...iced the keyAt(index) function.
So I'll go with something like this:
for(int i = 0; i < sparseArray.size(); i++) {
int key = sparseArray.keyAt(i);
// get the object by the key.
Object obj = sparseArray.get(key);
}
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Java: how can I split an ArrayList in multiple small ArrayLists?
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You can use subList(int fromIndex, int toIndex) to get a view of a portion of the original list.
From the API:
Returns a view of the portion of this list between the specified fromIndex, inclusive, and toIndex, exclusive. (If fromIndex and ...
Pick a random element from an array
...umed against previously.
let array = ["Frodo", "Sam", "Wise", "Gamgee"]
print(array.randomElement()!) // Using ! knowing I have array.count > 0
If you don't create the array and aren't guaranteed count > 0, you should do something like:
if let randomElement = array.randomElement() {
p...
Find size of object instance in bytes in c#
... or major .NET update.
You can use the information in this article on CLR internals MSDN Magazine Issue 2005 May - Drill Into .NET Framework Internals to See How the CLR Creates Runtime Objects - last I checked, it was still applicable. Here's how this is done (it retrieves the internal "Basic Inst...
How do you round a number to two decimal places in C#?
...per to specify the type of rounding (Round-to-even or Away-from-zero). The Convert.ToInt32() method and its variations use round-to-even. The Ceiling() and Floor() methods are related.
You can round with custom numeric formatting as well.
Note that Decimal.Round() uses a different method than Mat...
PHP - iterate on string characters
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Step 1: convert the string to an array using the str_split function
$array = str_split($your_string);
Step 2: loop through the newly created array
foreach ($array as $char) {
echo $char;
}
You can check the PHP docs for more in...
How to increment a pointer address and pointer's value?
...crements first and then returns it.
Third, by increasing the value of a pointer, you're incrementing it by the sizeof its contents, that is you're incrementing it as if you were iterating in an array.
So, to sum it all up:
ptr++; // Pointer moves to the next int position (as if it was an array...