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How to check if std::map contains a key without doing insert?
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Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.
Alternately my_map.find( key ) != my_map.end() works too.
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How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?
...t an int to String, make use of String#valueOf().
If your intent is after all to arrange and display them in a human friendly string format, then better use either Java8's java.time.format.DateTimeFormatter (tutorial here),
LocalDateTime now = LocalDateTime.now();
String format1 = now.format(DateTi...
How to customize a Spinner in Android
...er"
android:src="@mipmap/drop" />
</RelativeLayout>
Finally looks like below image and it is everywhere clickable in round area and no need to write click Lister for imageView.
Step3: For drop-down design, remove the line from Dropdown ListView and change the background color,...
insert multiple rows via a php array into mysql
...like you might be running into string-handling problems in PHP, which is really an algorithm problem, not a language one. Basically, when working with large strings, you want to minimize unnecessary copying. Primarily, this means you want to avoid concatenation. The fastest and most memory efficient...
Targeting position:sticky elements that are currently in a 'stuck' state
...an intersection observer to notify when elements with the class
* `.sticky_sentinel--top` become visible/invisible at the top of the container.
* @param {!Element} container
*/
function observeHeaders(container) {
const observer = new IntersectionObserver((records, observer) => {
for (co...
How do I parse command line arguments in Java?
What is a good way of parsing command line arguments in Java?
20 Answers
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Direct casting vs 'as' operator?
... tend to almost never use 2 since if something is not the right type, I usually expect an exception to occur. I have only seen a need for this return-null type of functionality with badly designed libraries which use error codes (e.g. return null = error, instead of using exceptions).
3 is not a ca...
NSDictionary - Need to check whether dictionary contains key-value pair or not
...uldn't we mistakenly think that the key isn't present in the dictionary at all?
– jbx72487
Feb 1 '13 at 18:51
13
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Escape string for use in Javascript regex [duplicate]
...mp;'); // $& means the whole matched string
}
Example
escapeRegExp("All of these should be escaped: \ ^ $ * + ? . ( ) | { } [ ]");
>>> "All of these should be escaped: \\ \^ \$ \* \+ \? \. \( \) \| \{ \} \[ \] "
(NOTE: the above is not the original answer; it was edited to show th...
Python initializing a list of lists [duplicate]
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The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the sam...