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Using Java 8 to convert a list of objects into a string obtained from the toString() method
...d guess that iterative string concatenation (reduction) requires array (re)allocation at each iteration, which makes it O(n^2). join on the other side would preallocate a single array large enough to store the final string before populating it, making it O(n).
– Eli Korvigo
...
Query to list number of records in each table in a database
... i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
WHERE
t.NAME NOT LIKE 'dt%' AND
i.OBJECT_ID > 255 AND
i.index_id <= 1
GROUP BY
t.NAME, i.object_id, i.index_id, i.name, p.[Rows]
ORDER BY
o...
Looping a video with AVFoundation AVPlayer?
...and in its selector, loop your video
AVPlayerItem *video = [[AVPlayerItem alloc] initWithURL:videoURL];
[self.player insertItem:video afterItem:nil];
[self.player play];
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improve this answe...
Cell spacing in UICollectionView
... to zero.
UICollectionViewFlowLayout *flow = [[UICollectionViewFlowLayout alloc] init];
flow.itemSize = CGSizeMake(cellWidth, cellHeight);
flow.scrollDirection = UICollectionViewScrollDirectionHorizontal;
flow.minimumInteritemSpacing = 0;
flow.minimumLineSpacing = 0;
Also, if all your cells are t...
How can I create a two dimensional array in JavaScript?
...st dimension values initialized to run .map. Remember that Array will not allocate the positions until you order it to through .fill or direct value assignment.
var arr = Array(2).fill(null).map(() => Array(4));
arr[0][0] = 'foo';
console.info(arr);
Follow up
Here's a method tha...
UIButton Image + Text IOS
.../You can replace it with your own dimensions.
UILabel *label=[[UILabel alloc] initWithFrame:CGRectMake(0.0f, 35.0f, 50.0f, 44.0f)];///You can replace it with your own dimensions.
[button addSubview:label];
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Mongoose (mongodb) batch insert?
...
insertMany doesn't work for me. I got a fatal error allocation failed. But if I use collection.insert It works perfectly.
– John
Dec 12 '16 at 13:03
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MySQL high CPU usage [closed]
...db_buffer_pool_size (if you're using innodb tables) as all of these memory allocations can have an affect on query performance which can cause MySQL to eat up CPU.
You'll also probably want to give the following a read over as they contain some good information.
How MySQL Uses Memory
MySQL System...
How do I split a multi-line string into multiple lines?
...An advantage to this method, when compared to str.split, is not needing to allocate any memory (it reads the string in-place). A disadvantage is that it's much slower if you use StringIO (about 50x). If you use cStringIO, however, it's about 2x faster
– goncalopp
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Remove element of a regular array
... another array" - per the linked documentation, Array.Resize actually does allocate a new array behind the scenes, and copies the elements from the old array to the new one. Still, I like the conciseness of this solution.
– Jon Schneider
Sep 11 '14 at 14:48
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