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Create a dictionary with list comprehension
...(key)) for key in keys)
In simple cases you don't need a comprehension at all...
But if you already have iterable(s) of keys and/or values, just call the dict built-in directly:
1) consumed from any iterable yielding pairs of keys/vals
dict(pairs)
2) "zip'ped" from two separate iterables of keys/v...
Best ways to teach a beginner to program? [closed]
...and I'll be doing an after school workshop with high school students this fall. This is the closest thing I've got to documentation. It's still a work in progress, but I hope it helps.
1) FizzBuzz. Start with command line programs. You can write some fun games, or tools, very quickly, and you learn...
Cleanest way to build an SQL string in Java
...
First of all consider using query parameters in prepared statements:
PreparedStatement stm = c.prepareStatement("UPDATE user_table SET name=? WHERE id=?");
stm.setString(1, "the name");
stm.setInt(2, 345);
stm.executeUpdate();
The ...
How do I run a program with a different working directory from current, from Linux shell?
...
Call the program like this:
(cd /c; /a/helloworld)
The parentheses cause a sub-shell to be spawned. This sub-shell then changes its working directory to /c, then executes helloworld from /a. After the program exits, the sub...
Difference between `constexpr` and `const`
...zation.
constexpr declares an object as fit for use in what the Standard calls constant expressions. But note that constexpr is not the only way to do this.
When applied to functions the basic difference is this:
const can only be used for non-static member functions, not functions in general. I...
combinations between two lists?
...aving trouble wrapping my head around a algorithm I’m try to make. Basically, I have two lists and want to get all the combinations of the two lists.
...
What is the purpose and use of **kwargs?
...t_name = John
last_name = Doe
You can also use the **kwargs syntax when calling functions by constructing a dictionary of keyword arguments and passing it to your function:
>>> kwargs = {'first_name': 'Bobby', 'last_name': 'Smith'}
>>> print_keyword_args(**kwargs)
first_name = B...
Why I cannot cout a string?
...-defined <xstring> header (never include that directly)). While that allows you to use the string class, the relevant operator<< is defined in the <string> header itself, so you must include that manually. Also relying on other headers to indirectly include the definition of std::b...
What is the difference between “INNER JOIN” and “OUTER JOIN”?
...b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUTER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b(+);
a | b
--+-----
1 | null
2 | null
3 | 3
4 | 4
Right outer join
A right outer j...
How to recursively delete an entire directory with PowerShell 2.0?
What is the simplest way to forcefully delete a directory and all its subdirectories in PowerShell? I am using PowerShell V2 in Windows 7.
...