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Unique (non-repeating) random numbers in O(1)?
... max
At each iteration, a random number r is selected between 0 and max, array[r] and array[max] are swapped, the new array[max] is returned, and max is decremented:
max = 10, r = 3
+--------------------+
v v
+--+--+--+--+--+--+...
Mysql adding user for remote access
... that you have to create or update a user. look for all your mysql users:
SELECT user,password,host FROM user;
as soon as you got your user set up you should be able to connect like this:
mysql -h localhost -u gmeier -p
hope it helps
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Android - Emulator in landscape mode, screen does not rotate
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In my case the Skin option in AVD settings was the problem. When I selected "No skin", it worked.
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Avoiding “resource is out of sync with the filesystem”
...lesystem” this problem happens when I use external workspace, so after I select this option, problem solved.
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How do I find the location of my Python site-packages directory?
...ib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and see python -m site --help for explanations.
Hint: Running pip list --user or pip freeze -...
Best practices with STDIN in Ruby?
...ARGF is your friend when it comes to input; it is a virtual file that gets all input from named files or all from STDIN.
ARGF.each_with_index do |line, idx|
print ARGF.filename, ":", idx, ";", line
end
# print all the lines in every file passed via command line that contains login
ARGF.each do...
correct way to define class variables in Python [duplicate]
... being init always executed after the object is created, it becomes practically equal to define variables outside of init, right?
– jeanc
Jan 29 '12 at 21:33
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Comparing strings with == which are declared final in Java
...nal and initialized with a compile-time constant expression (§15.28), is called a constant variable.
Also from JLS §15.28 - Constant Expression:
Compile-time constant expressions of type String are always "interned" so as to share unique instances, using the method String#intern().
This ...
Does Foreign Key improve query performance?
...the foreign key relationship already inforces that for you.
So this:
select p.ProductId, p.Name, c.CategoryId, c.Name AS Category
from Products p inner join ProductCategories c on p.CategoryId = c.CategoryIdwhere c.CategoryId = 1;
Becomes this:
SELECT p.ProductId, p.Name, c.CategoryId, c.N...
How to identify numpy types in python?
...o test for that. And so on. The point is, you have to know what you're actually asking for when you want to do something as unusual as loose manual type switching, but once you know, it's easy to implement.
– abarnert
Mar 11 '16 at 20:41
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