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Most efficient way to remove special characters from string
...ms.
The price to pay is, of course, the initialization of the huge lookup table and keeping it in memory. Well, it's not that much data, but it's much for such a trivial function...
private static bool[] _lookup;
static Program() {
_lookup = new bool[65536];
for (char c = '0'; c <= '9'; ...
Is there any advantage of using map over unordered_map in case of trivial keys?
...f course) when using unordered_map instead of map in a main entity look-up table.
On the other hand, I found it was much slower at repeatedly inserting and removing elements. It's great for a relatively static collection of elements, but if you're doing tons of insertions and deletions the hashing ...
Cast int to varchar
...wing SQL — in action — over at SQL Fiddle:
/*! Build Schema */
create table t9 (id INT, name VARCHAR(55));
insert into t9 (id, name) values (2, 'bob');
/*! SQL Queries */
select CAST(id as CHAR(50)) as col1 from t9;
select CONVERT(id, CHAR(50)) as colI1 from t9;
Besides the fact that you w...
Vertical (rotated) text in HTML table
Is there a (portable) way to rotate text in a HTML table cell by 90°?
11 Answers
11
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What is the difference between MOV and LEA?
...is answer is basically wrong because the question is asking about MOV AX, [TABLE-ADDR], which is a load. So there is a major difference. The equivalent instruction is mov ax, OFFSET table_addr
– Peter Cordes
Feb 27 '18 at 23:56
...
How to return result of a SELECT inside a function in PostgreSQL?
...ERY:
CREATE OR REPLACE FUNCTION word_frequency(_max_tokens int)
RETURNS TABLE (txt text -- also visible as OUT parameter inside function
, cnt bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
, count(*) AS cnt -- co...
What is NSLayoutConstraint “UIView-Encapsulated-Layout-Height” and how should I go about forcing it
I have a UITableView running under iOS 8 and I'm using automatic cell heights from constraints in a storyboard.
17 Answer...
What is the most ridiculous pessimization you've seen? [closed]
...
Databases are pessimization playland.
Favorites include:
Split a table into multiples (by date range, alphabetic range, etc.) because it's "too big".
Create an archive table for retired records, but continue to UNION it with the production table.
Duplicate entire databases by (division/cus...
PostgreSQL - max number of parameters in “IN” clause?
... possible if the inputs are all scalars (no RowExprs) and there is a
* suitable array type available. If not, we fall back to a boolean
* condition tree with multiple copies of the lefthand expression.
* Also, any IN-list items that contain Vars are handled as separate
* boolean conditions, bec...
Remove columns from dataframe where ALL values are NA
... function to reduce the size. The answer bellow using Filter or using data.table will help your memory usage.
– mtelesha
Dec 9 '15 at 15:21
3
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