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How is this fibonacci-function memoized?
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The evaluation mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for...
Android Fragment lifecycle over orientation changes
Using the compatibility package to target 2.2 using Fragments.
7 Answers
7
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String literals: Where do they go?
I am interested in where string literals get allocated/stored.
8 Answers
8
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Doctrine - How to print out the real sql, not just the prepared statement?
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Doctrine is not sending a "real SQL query" to the database server : it is actually using prepared statements, which means :
Sending the statement, for it to be prepared (this is what is returned by $query->getSql())
And, then, sending the parameters (returned by $query->getParameters(...
E11000 duplicate key error index in mongodb mongoose
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The error message is saying that there's already a record with null as the email. In other words, you already have a user without an email address.
The relevant documentation for this:
If a document does not have a value for the indexed field in a unique index, the index will store ...
What's the best way to do a backwards loop in C/C#/C++?
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While admittedly a bit obscure, I would say that the most typographically pleasing way of doing this is
for (int i = myArray.Length; i --> 0; )
{
//do something
}
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Python: Find in list
...As for your first question: that code is perfectly fine and should work if item equals one of the elements inside myList. Maybe you try to find a string that does not exactly match one of the items or maybe you are using a float value which suffers from inaccuracy.
As for your second question: Ther...
Handling optional parameters in javascript
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edited Aug 20 '12 at 0:08
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Picking a random element from a set
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int size = myHashSet.size();
int item = new Random().nextInt(size); // In real life, the Random object should be rather more shared than this
int i = 0;
for(Object obj : myhashSet)
{
if (i == item)
return obj;
i++;
}
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Error 908: Permission Receive SMS - #5 by Taifun - MIT App Inventor Help - MIT App Inventor Community
...a theme a light scheme and also enabled a dark scheme */
/* deal with light scheme first */
@media (prefers-color-scheme: light) {
:root {
--primary: #222222;
--secondary: #ffffff;
--tertiary: #0088cc;
--quaternary: #e45735;
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