大约有 40,200 项符合查询结果（耗时：0.0602秒） [XML]
Why does base64 encoding require padding if the input length is not divisible by 3?
What is the purpose of padding in base64 encoding. The following is the extract from wikipedia:
3 Answers
...
What is the difference between packaged_task and async
...scribes the insights. Also do note that this behavior was specified in C++14 and up, but also commonly implemented in C++11.
Further differences
By using std::async you cannot run your task on a specific thread anymore, where std::packaged_task can be moved to other threads.
std::packaged_task<...
Looking for a clear definition of what a “tokenizer”, “parser” and...
...
4 Answers
4
Active
...
Is it safe to ignore the possibility of SHA collisions in practice?
...256 (n=256) and one billion messages (p=109) then the probability is about 4.3*10-60.
A mass-murderer space rock happens about once every 30 million years on average. This leads to a probability of such an event occurring in the next second to about 10-15. That's 45 orders of magnitude more probabl...
What is private bytes, virtual bytes, working set?
...
4 Answers
4
Active
...
Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
...ion on my system is 1 µs, but I also tested it on a Linux system (Red Hat 4.1.2-48 with GCC 4.1.2) and there the precision was only 1 ms.
gettimeofday() returns the wall-clock time with (nominally) µs precision. On my system this clock does seem to have µs precision, but this is not guaranteed, b...
Adding 'serial' to existing column in Postgres
...
134
Look at the following commands (especially the commented block).
DROP TABLE foo;
DROP TABLE bar...
What is the usefulness of PUT and DELETE HTTP request methods?
...
4 Answers
4
Active
...
How do you track record relations in NoSQL?
...
4 Answers
4
Active
...
Foreign keys in mongo?
...{group:"phones"})
> db.foo.find()
{ "_id" : ObjectId("4df6539ae90592692ccc9940"), "group" : "phones" }
{ "_id" : ObjectId("4df6540fe90592692ccc9941"), "group" : "phones" }
>db.foo.find({'_id':ObjectId("4df6539ae90592692ccc9940")})
{ "_id" : ObjectId("4df6539ae90592692ccc9940...