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Practical uses of different data structures [closed]
...ght accent at all. You need to understand not just which data structure to select, but some other points to consider when people think about data structures:
pros and cons of the common data structures
why each data structure exist
how it actually work in the memory
specific questions/exe...
What does void* mean and how to use it?
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Before void pointers were available "char *" was used instead. But void is better as it cannot actually be used to alter anything directly.
– user50619
Jun 4 '19 at 13:08
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How to check for a valid Base64 encoded string
...s pretty easy to recognize a Base64 string, as it will only be composed of characters 'A'..'Z', 'a'..'z', '0'..'9', '+', '/' and it is often padded at the end with up to three '=', to make the length a multiple of 4. But instead of comparing these, you'd be better off ignoring the exception, if it o...
What is the maximum number of characters that nvarchar(MAX) will hold?
I'm new to the concept nvarchar(MAX) . How many characters will it hold?
3 Answers
3
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How to filter SQL results in a has-many-through relation
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Results:
Total runtimes from EXPLAIN ANALYZE.
1) Martin 2: 44.594 ms
SELECT s.stud_id, s.name
FROM student s
JOIN student_club sc USING (stud_id)
WHERE sc.club_id IN (30, 50)
GROUP BY 1,2
HAVING COUNT(*) > 1;
2) Erwin 1: 33.217 ms
SELECT s.stud_id, s.name
FROM student s
JOIN ...
Java executors: how to be notified, without blocking, when a task completes?
... {
sleep(7000, TimeUnit.MILLISECONDS); /* Pretend to be busy... */
char[] str = new char[5];
ThreadLocalRandom current = ThreadLocalRandom.current();
for (int idx = 0; idx < str.length; ++idx)
str[idx] = (char) ('A' + current.nextInt(26));
String msg = new String(str);
...
How can I negate the return-value of a process?
...#include <sys/wait.h>
#include "stderr.h"
#ifndef lint
static const char sccs[] = "@(#)$Id: not.c,v 4.2 2005/06/22 19:44:07 jleffler Exp $";
#endif
int main(int argc, char **argv)
{
int pid;
int corpse;
int status;
err_setarg0(argv[0]);
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Git 工具 - 子模块(submodule)：一个仓库包含另一个仓库 - 开源 & Github -...
.../src/main.c
@@ -245,6 +245,8 @@ static int handle_alias(int *argcp, const char ***argv)
commit_pager_choice();
+ url = url_decode(url_orig);
+
/* build alias_argv */
alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
alias_argv[0] = alias_string + 1;
Ente...
How to read from a file or STDIN in Bash?
...ter to add -r to your read command, so that it doesn't accidentally eat \ chars; use while IFS= read -r line to preserve leading and trailing whitespace.
– mklement0
Feb 28 '15 at 23:34
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Where is PATH_MAX defined in Linux?
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Its in linux/limits.h.
#define PATH_MAX 4096 /* # chars in a path name including nul */
#include <linux/limits.h>
char current_path[PATH_MAX];
PATH_MAX has some flaws as mentioned in this blog (thanks paulsm4)
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