大约有 47,000 项符合查询结果（耗时：0.0637秒） [XML]
Will using goto leak variables?
...
210
Warning: This answer pertains to C++ only; the rules are quite different in C.
Won't x be ...
Move an item inside a list?
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answered Jul 3 '10 at 23:15
David ZDavid Z
111k2323 gold badges218218 silver badges256256 bronze badges
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Join strings with a delimiter only if strings are not null or empty
...ple:
[...].filter(x => typeof x === 'string' && x.length > 0)
will only keep non-empty strings in the list.
--
(obsolete jquery answer)
var address = "foo";
var city;
var state = "bar";
var zip;
text = $.grep([address, city, state, zip], Boolean).join(", "); // foo, bar
...
How to initialize a vector in C++ [duplicate]
...is with an array:
int vv[2] = { 12,43 };
std::vector<int> v(&vv[0], &vv[0]+2);
Or, for the case of assignment to an existing vector:
int vv[2] = { 12,43 };
v.assign(&vv[0], &vv[0]+2);
Like James Kanze suggested, it's more robust to have functions that give you the beginni...
How to prevent page scrolling when scrolling a DIV element?
...'.scrollable' ).on( 'mousewheel DOMMouseScroll', function ( e ) {
var e0 = e.originalEvent,
delta = e0.wheelDelta || -e0.detail;
this.scrollTop += ( delta < 0 ? 1 : -1 ) * 30;
e.preventDefault();
});
Live demo: https://jsbin.com/howojuq/edit?js,output
So you manually set t...
Code Golf: Collatz Conjecture
Inspired by http://xkcd.com/710/ here is a code golf for it.
70 Answers
70
...
How do I convert an integer to binary in JavaScript?
...
function dec2bin(dec){
return (dec >>> 0).toString(2);
}
dec2bin(1); // 1
dec2bin(-1); // 11111111111111111111111111111111
dec2bin(256); // 100000000
dec2bin(-256); // 11111111111111111111111100000000
You can use Number.toString(2) function, but it has ...
Printf width specifier to maintain precision of floating-point value
...n:
#include <float.h>
int Digs = DECIMAL_DIG;
double OneSeventh = 1.0/7.0;
printf("%.*e\n", Digs, OneSeventh);
// 1.428571428571428492127e-01
But let's dig deeper ...
Mathematically, the answer is "0.142857 142857 142857 ...", but we are using finite precision floating point numbers.
Let...
Python to print out status bar and percentage
...t progressbar
from time import sleep
bar = progressbar.ProgressBar(maxval=20, \
widgets=[progressbar.Bar('=', '[', ']'), ' ', progressbar.Percentage()])
bar.start()
for i in xrange(20):
bar.update(i+1)
sleep(0.1)
bar.finish()
To install it, you can use easy_install progressbar, or pip ...
How to read data from a zip file without having to unzip the entire file
...n zip)
{
if (header)
{
System.Console.WriteLine("Zipfile: {0}", zip.Name);
if ((zip.Comment != null) && (zip.Comment != ""))
System.Console.WriteLine("Comment: {0}", zip.Comment);
System.Console.WriteLine("\n{1,-22} {2,8} {3,5} {4,8} {5,3} {0}",
...