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'printf' vs. 'cout' in C++
... You say I/O is the bottleneck anyway. Obviously you never tested that assumption. I quote myself: "On the other hand, the iostreams version, at 75.3 MB/s, can't buffer data fast enough to keep up with a hard disk. That's bad, and it's not even doing any real work yet. I don't think...
MySQL: Sort GROUP_CONCAT values
....html#function_group-concat:
SELECT student_name,
GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
FROM student
GROUP BY student_name;
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Once upon a time, when > was faster than < … Wait, what?
... what's it all about, the author mentions that we can perform custom depth tests, such as GL_LESS, GL_ALWAYS, etc. He also explains that the actual meaning of depth values (which is top and which isn't) can also be customized. I understand so far. And then the author says something unbelievable:
...
Can a for loop increment/decrement by more than one?
...
A for loop:
for(INIT; TEST; ADVANCE) {
BODY
}
Means the following:
INIT;
while (true) {
if (!TEST)
break;
BODY;
ADVANCE;
}
You can write almost any expression for INIT, TEST, ADVANCE, and BODY.
Do note that the ++ ope...
How to copy a file to a remote server in Python using SCP or SSH?
...t('example.com')
with SCPClient(ssh.get_transport()) as scp:
scp.put('test.txt', 'test2.txt')
scp.get('test2.txt')
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Why is subtracting these two times (in 1927) giving a strange result?
...cause I'm collecting questions like this in Noda Time, in the form of unit tests... The test has now been changed, but it just goes to show - not even historical data is safe.
EDIT: History has changed again...
In TZDB 2014f, the time of the change has moved to 1900-12-31, and it's now a mere 343 ...
Is “else if” faster than “switch() case”? [duplicate]
...ement does not rely on earlier cases, the compiler is able to re-order the testing in such a way as to provide the fastest execution.
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How to disable scrolling temporarily?
...adding event
var supportsPassive = false;
try {
window.addEventListener("test", null, Object.defineProperty({}, 'passive', {
get: function () { supportsPassive = true; }
}));
} catch(e) {}
var wheelOpt = supportsPassive ? { passive: false } : false;
var wheelEvent = 'onwheel' in document.c...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...simple:
-- THIS IS WRONG. DO NOT COPY IT. It's an EXAMPLE.
BEGIN;
UPDATE testtable
SET somedata = 'blah'
WHERE id = 2;
-- Remember, this is WRONG. Do NOT COPY IT.
INSERT INTO testtable (id, somedata)
SELECT 2, 'blah'
WHERE NOT EXISTS (SELECT 1 FROM testtable WHERE testtable.id = 2);
COMMIT;
th...
jQuery Datepicker onchange event issue
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Has anyone tested this recently? It doesn't work for me. i.lastVal returns undefined and it doesn't appear to be one of the available properties.
– B.K.
Oct 29 '14 at 2:13
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