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Structs versus classes
I'm about to create 100,000 objects in code. They are small ones, only with 2 or 3 properties. I'll put them in a generic list and when they are, I'll loop them and check value a and maybe update value b .
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What is the best place for storing uploaded images, SQL database or disk file system? [closed]
I'm writing an application that allows users to upload images onto the server. I expect about 20 images per day all jpeg and probably not edited/resized. (This is another question, how to resize the images on the server side before storing. Maybe someone can please drop a .NET resource for that in t...
Practical use of `stackalloc` keyword
Has anyone ever actually used stackalloc while programming in C#? I am aware of what is does, but the only time it shows up in my code is by accident, because Intellisense suggests it when I start typing static , for example.
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Explain the use of a bit vector for determining if all characters are unique
...ge for bits. Every bit in integer value can be treated as a flag, so eventually int is an array of bits (flag). Each bit in your code states whether the character with bit's index was found in string or not. You could use bit vector for the same reason instead of int. There are two differences betwe...
Is there any way to put malicious code into a regular expression?
...o solve. These may only show up on particular input data, but one can generally create one wherein this doesn’t matter.
Which ones these are will depend somewhat on how smart the regex compiler you’re using happens to be, because some of these can be detected during compilation time. Regex com...
IN vs OR in the SQL WHERE Clause
...ds a much more complex evaluation process than the IN construct because it allows many conditions, not only equals like IN.
Here is a like of what you can use with OR but that are not compatible with IN:
greater. greater or equal, less, less or equal, LIKE and some more like the oracle REGEXP_LIKE...
Why does direction of index matter in MongoDB?
...d query in the same order as the index will simply return the rows sequentially in the correct order.
Finding a record in a BTree takes O(Log(n)) time. Finding a range of records in order is only OLog(n) + k where k is the number of records to return.
If the records are out of order, the cost coul...
Java HashMap performance optimization / alternative
...={99,100}) will hash to the same value as (a[]={3,1,2}, b[]={100,99}). Actually all keys k1 and k2 where sum(k1.a)==sum(k2.a) and sum(k1.b)=sum(k2.b) will result in collisions. I suggest assigning a weight to each position of the array:
hash = hash * 5381 + (c0*a[0] + c1*a[1]);
hash = hash * 5381 +...
AI2 Media Notification
...in several apps, tapping an action button triggers the associated event in all apps at the same time. This is due to the global nature of the broadcast receivers used. Solution: The intents for the action buttons are individualized with the app name. When a broadcast is received, the name is c...
Do you have to put Task.Run in a method to make it async?
... numbers for the sake of this example, granted, it's no processing time at all, it's just a matter of formulating an example here.
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