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What are the underlying data structures used for Redis?
...m-ish unique users") or with replacement ("give me 7 cards, but after each selection, put the card back so it can potentially be sampled again").
For all possible operations on sets, see the sets docs.
Sorted Sets
Redis sorted sets are sets with a user-defined ordering.
For simplicity, you can think...
Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...n multiple courses, books, and jobs, I have seen text fields defined as VARCHAR(255) as kind of the default for "shortish" text. Is there any good reason that a length of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a goo...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
... /* modify variable */
variable = 1;
}
}
int main(int argc, char **argv) {
if (modifies_variable(f, variable)) {
printf("Modifies variable\n");
} else {
printf("Does not modify variable\n");
}
return 0;
}
...
Check if a string contains another string
...ontains a ","(comma) in it. Do we have any other option other than reading char-by-char?
4 Answers
...
SVG get text element width
...a try. I decided to generate constant values for each individual printable character. Normally this would be kind of tedious, but luckily Firefox happens to be super accurate. Here is my two part brute force solution:
<body>
<script>
var div = doc...
How to Calculate Execution Time of a Code Snippet in C++
...;boost/progress.hpp>
using namespace boost;
int main (int argc, const char * argv[])
{
progress_timer timer;
// do stuff, preferably in a 100x loop to make it take longer.
return 0;
}
When progress_timer goes out of scope it will print out the time elapsed since its creation.
UPDATE:...
Polymorphism in C++
...egorise them in various ways:
When is the polymorphic type-specific code selected?
Run time means the compiler must generate code for all the types the program might handle while running, and at run-time the correct code is selected (virtual dispatch)
Compile time means the choice of type-specif...
How to write iOS app purely in C
... full function declaration, like this:
// int UIApplicationMain (int argc, char *argv[], NSString *principalClassName, NSString *delegateClassName);
// So, we rely on the fact that for both the i386 & ARM architectures,
// the registers for parameters passed in remain the same whether or not
/...
What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?
...minal is historically slow (terminals or consoles are still slow), writing character by character is ineffective, writing a chunk of bytes is much more effective.
– Some programmer dude
Apr 4 '18 at 17:23
...
Efficient way to return a std::vector in c++
...
vector<string> getseq(char * db_file)
And if you want to print it on main() you should do it in a loop.
int main() {
vector<string> str_vec = getseq(argv[1]);
for(vector<string>::iterator it = str_vec.begin(); it != str_ve...