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Fast permutation -> number -> permutation mapping algorithms
I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
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How to resolve “must be an instance of string, string given” prior to PHP 7?
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Madbreaks
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answered Nov 5 '10 at 4:09
deceze♦deceze
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How to download Xcode DMG or XIP file?
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4943
You can find the DMGs or XIPs for Xcode and other development tools on https://developer.appl...
Annotating text on individual facet in ggplot2
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147
+50
Typicall...
Get element inside element by class and ID - JavaScript
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242
Well, first you need to select the elements with a function like getElementById.
var targetDiv...
Best data type for storing currency values in a MySQL database
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Something like Decimal(19,4) usually works pretty well in most cases. You can adjust the scale and precision to fit the needs of the numbers you need to store. Even in SQL Server, I tend not to use "money" as it's non-standard.
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Eclipse Android Plugin — libncurses.so.5
...htily with installing ADT (Android Dev Tools) on Eclipse in Fedora 16 OS, 64-bit.
7 Answers
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How to ignore xargs commands if stdin input is empty?
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kenorb
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answered Nov 28 '11 at 13:49
Sven MarnachSve...
How to force LINQ Sum() to return 0 while source collection is empty
...imon Belanger
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How do I remove duplicate items from an array in Perl?
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You can do something like this as demonstrated in perlfaq4:
sub uniq {
my %seen;
grep !$seen{$_}++, @_;
}
my @array = qw(one two three two three);
my @filtered = uniq(@array);
print "@filtered\n";
Outputs:
one two three
If you want to use a module, try the uniq func...