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What is the difference between std::array and std::vector? When do you use one over other? [duplicat
...t. Creating large objects on the stack is generally frowned upon, and the extra level of indirection is usually irrelevant. (For example, if you iterate through all of the elements, the extra memory access only happens once at the start of the loop.)
The vector's elements are guaranteed to be con...
Why does this code using random strings print “hello world”?
...e share your code. I would greatly appreciate it.
public static void main(String[] args) {
long time = System.currentTimeMillis();
generate("stack");
generate("over");
generate("flow");
generate("rulez");
System.out.println("Took " + (System.currentTimeMillis() - time) + " ...
How to Calculate Execution Time of a Code Snippet in C++
...without Boost (tested on macOS/iOS):
#include <chrono>
#include <string>
#include <iostream>
#include <math.h>
#include <unistd.h>
class NLTimerScoped {
private:
const std::chrono::steady_clock::time_point start;
const std::string name;
public:
NLTimerSco...
What is the C# equivalent of NaN or IsNumeric?
What is the most efficient way of testing an input string whether it contains a numeric value (or conversely Not A Number)? I guess I can use Double.Parse or a regex (see below) but I was wondering if there is some built in way to do this, such as javascript's NaN() or IsNumeric() (was that VB...
strdup() - what does it do in C?
...ed to the abbreviated way in which C and UNIX assigns words, it duplicates strings :-)
Keeping in mind it's actually not part of the ISO C standard itself(a) (it's a POSIX thing), it's effectively doing the same as the following code:
char *strdup(const char *src) {
char *dst = malloc(strlen (...
Test whether string is a valid integer
...aining it so I can learn a little? I gather it reads, "At the start of the string (^), a minus sign (-) is optional (?), followed by any number of characters between zero and 9, inclusive" ... and what then might the +$ mean? Thanks.
– Richard T
Feb 5 '10 at 21...
Format XML string to print friendly XML string
I have an XML string as such:
9 Answers
9
...
How does functools partial do what it does?
...e code more readable. re.search method's signature is:
search(pattern, string, flags=0)
By applying partial we can create multiple versions of the regular expression search to suit our requirements, so for example:
is_spaced_apart = partial(re.search, '[a-zA-Z]\s\=')
is_grouped_together = ...
Count the number of occurrences of a string in a VARCHAR field?
...
The ROUND here is unnecessary. assume a string of length x with n occurrences of'value. LENGTH(description) - LENGTH( REPLACE ( description, "value", "") ) will always give you n*length("value"), diving that by length of value will always leave a whole number n. N...
How to convert a data frame column to numeric type?
... char_fac = factor(letters[1:5]),
num = 1:5, stringsAsFactors = FALSE)
Let us have a glance at data.frame
> d
char fake_char fac char_fac num
1 a 1 1 a 1
2 b 2 2 b 2
3 c 3 3 c 3
4 d 4 ...