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Simple explanation of MapReduce?
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Going all the way down to the basics for Map and Reduce.
Map is a function which "transforms" items in some kind of list to another kind of item and put them back in the same kind of list.
suppose I have a list of numbers: [1,2...
Are C++ enums signed or unsigned?
...integral type is used as the underlying type for an enum, except that it shall not be larger than int, unless some value cannot fit into int or an unsigned int.
In short: you cannot rely on an enum being either signed or unsigned.
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SQL exclude a column using SELECT * [except columnA] FROM tableA?
We all know that to select all columns from a table, we can use
41 Answers
41
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Regexp Java for password validation
...ecial character must occur at least once
(?=\S+$) # no whitespace allowed in the entire string
.{8,} # anything, at least eight places though
$ # end-of-string
It's easy to add, modify or remove individual rules, since every rule is an independent "module".
Th...
What is a 'Closure'?
... scope
When you declare a local variable, that variable has a scope. Generally, local variables exist only within the block or function in which you declare them.
function() {
var a = 1;
console.log(a); // works
}
console.log(a); // fails
If I try to access a local variable, most languag...
How can I use Google's Roboto font on a website?
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You don't really need to do any of this.
Go to Google's Web Fonts page
search for Roboto in the search box at the top right
Select the variants of the font you want to use
click 'Select This Font' at the top and choose the weights an...
Intellij IDEA, format all code in a project
I really like IDEA's code formatting, but how do I get it to reformat all the code in a particular project without going through each file? I've found the option to tidy / optimise imports on code before committing it to subversion which is great, but it only seems to apply to files that have otherw...
in_array multiple values
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if(count(array_intersect($haystack, $target)) == count($target)){
// all of $target is in $haystack
}
Note that you only need to verify the size of the resulting intersection is the same size as the array of target values to say that $haystack is a superset of $target.
To verify that at lea...
How can I clear an HTML file input with JavaScript?
...d the file input element to this new form and reset it. This way works for all browsers.
I wrote a javascript function. demo: http://jsbin.com/muhipoye/1/
function clearInputFile(f){
if(f.value){
try{
f.value = ''; //for IE11, latest Chrome/Firefox/Opera...
}catch(...
ASP.NET MVC ambiguous action methods
I have two action methods that are conflicting. Basically, I want to be able to get to the same view using two different routes, either by an item's ID or by the item's name and its parent's (items can have the same name across different parents). A search term can be used to filter the list.
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