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HashMap get/put complexity
... assume the following three cases:
HashMap<Integer, V>
HashMap<String, V>
HashMap<List<E>, V>
Do they have the same complexity? Well, the amortised complexity of the 1st one is, as expected, O(1). But, for the rest, we also need to compute hashCode() of the lookup elemen...
MySQL DISTINCT on a GROUP_CONCAT()
...swers to this question do not return what the OP needs, they will return a string like:
test1 test2 test3 test1 test3 test4
(notice that test1 and test3 are duplicated) while the OP wants to return this string:
test1 test2 test3 test4
the problem here is that the string "test1 test3" is duplic...
How do I get the user agent with Flask?
...contains the following attributes which are created based on the useragent string:
platform (windows, linux, macos, etc.)
browser (chrome, firefox, msie, etc.)
version
language
string (== request.headers.get('User-Agent'))
...
How to save traceback / sys.exc_info() values in a variable?
...ionError"
exc_tuple[1] value will be "integer division or modulo by zero" (String passed as parameter to the exception class)
exc_tuple[2] value will be "trackback object at (some memory address)"
The above details can also be fetched by simply printing the exception in string format.
print str(...
External template in Underscore
... var tmpl_url = tmpl_dir + '/' + tmpl_name + '.html';
var tmpl_string;
$.ajax({
url: tmpl_url,
method: 'GET',
dataType: 'html', //** Must add
async: false,
success: function(data) {
tmpl_string = data;
...
What is a “slug” in Django?
.... Slugs are commonly save with the respective content and it pass as a URL string.
Slug can create using SlugField
Ex:
class Article(models.Model):
title = models.CharField(max_length=100)
slug = models.SlugField(max_length=100)
If you want to use title as slug, django has a simple func...
What is the difference between os.path.basename() and os.path.dirname()?
...ile name: here, 'foo.bar', and os.path.dirname(file_name) returns an empty string: ''.
– jkdev
Nov 26 '18 at 20:47
...
How to validate an email address using a regular expression?
...may not be exactly what you want to achieve. For example, it accepts these strings as valid e-mail addresses:
"user1@hotmail.com; user2@gmail.com"
"user1@hotmail.com; user2@gmail.com; user3@company.com"
"User Display Name user3@company.com"
"user4 @company.com"
In some of these cases, only the l...
Raise warning in Python without interrupting program
... @Tomas Novotny you can capture stdout and stderr, then check that the strings issued by your warning are found within.
– wheaties
Oct 8 '10 at 15:33
16
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Why can I initialize a List like an array in C#?
...onary<TKey, TValue> takes two items:
var grades = new Dictionary<string, int>
{
{ "Suzy", 100 },
{ "David", 98 },
{ "Karen", 73 }
};
Is roughly identical to:
var temp = new Dictionary<string, int>();
temp.Add("Suzy", 100);
temp.Add("David", 98);
...