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Can hash tables really be O(1)?
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You have two variables here, m and n, where m is the length of the input and n is the number of items in the hash.
The O(1) lookup performance claim makes at least two assumptions:
Your objects can be equality compared in O(1) time.
There will be few ha...
What is the best way to trigger onchange event in react js
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For React 16 and React >=15.6
Setter .value= is not working as we wanted because React library overrides input value setter but we can call the function directly on the input as context.
var nativeInputValueSetter = Object.getOwnProp...
How are echo and print different in PHP? [duplicate]
Is there any major and fundamental difference between these two functions in PHP?
5 Answers
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Which concurrent Queue implementation should I use in Java?
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Basically the difference between them are performance characteristics and blocking behavior.
Taking the easiest first, ArrayBlockingQueue is a queue of a fixed size. So if you set the size at 10, and attempt to insert an 11th element, the insert statement will block until another thread remove...
How to delete duplicates on a MySQL table?
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Notice: this would keep the oldest duplicate record and would erase the newer ones. If you want to keep the newest you cannot do this with ALTER IGNORE.
– Haralan Dobrev
Oct 1 '12 at 10:26
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C pointers : pointing to an array of fixed size
...orrect. I'd say that every C developer comes to exactly the same discovery and to exactly the same conclusion when (if) they reach certain level of proficiency with C language.
When the specifics of your application area call for an array of specific fixed size (array size is a compile-time constan...
What is the difference between Pan and Swipe in iOS?
...antics: a pan recognizer looks for the beginning of translational movement and continues to report movement in any direction over time, while a swipe recognizer makes an instantaneous decision as to whether the user's touches moved linearly in the required direction.
By default, no two recognizers...
Positions fixed doesn't work when using -webkit-transform
I am using -webkit-transform (and -moz-transform / -o-transform) to rotate a div. Also have position fixed added so the div scrols down with the user.
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Count(*) vs Count(1) - SQL Server
Just wondering if any of you people use Count(1) over Count(*) and if there is a noticeable difference in performance or if this is just a legacy habit that has been brought forward from days gone past?
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Curious null-coalescing operator custom implicit conversion behaviour
...hen there is a lifted conversion involving two nullable types on the left-hand side of the coalescing operator.
I have not yet identified where precisely things go wrong, but at some point during the "nullable lowering" phase of compilation -- after initial analysis but before code generation -- we...