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All combinations of a list of lists
I'm basically looking for a python version of Combination of List<List<int>>
7 Answers
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Why can't strings be mutable in Java and .NET?
...ctly one state, the state in which it was created. If you make sure
that all constructors establish class invariants, then it is
guaranteed that these invariants will remain true for all time, with
no effort on your part.
[...]
Immutable objects are inherently thread-safe; they requi...
Simple way to calculate median with MySQL
...ime finding a simple way of calculating the median. For now, I'm returning all the rows to PHP, doing a sort, and then picking the middle row, but surely there must be some simple way of doing it in a single MySQL query.
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Why doesn't Dictionary have AddRange?
...doesn't have any meaning to an associative container, as the range of data allows for duplicate entries. E.g if you had an IEnumerable<KeyValuePair<K,T>> that collection does not guard against duplicate entries.
The behavior of adding a collection of key-value pairs, or even merging tw...
Table overflowing outside of div
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This forces all of the columns to be the same width... not very useful
– Serj Sagan
Jul 9 '13 at 1:36
11
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How do I undo the most recent local commits in Git?
I accidentally committed the wrong files to Git , but I haven't pushed the commit to the server yet.
86 Answers
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PostgreSQL: Show tables in PostgreSQL
...terface,
First, choose your database
\c database_name
Then, this shows all tables in the current schema:
\dt
Programmatically (or from the psql interface too, of course):
SELECT * FROM pg_catalog.pg_tables;
The system tables live in the pg_catalog database.
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Access event to call preventdefault from custom function originating from onclick attribute of tag
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ok, I see all I had to do is to put my parameter second myfunc(event, {a:123, b:"asdas"})
– Omu
Dec 23 '11 at 10:01
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What is the difference between NULL, '\0' and 0?
...0 has different meanings depending upon the context in which it's used. In all cases, it is still an integer constant with the value 0, it is just described in different ways.
If a pointer is being compared to the constant literal 0, then this is a check to see if the pointer is a null pointer. Thi...
Understanding the Gemfile.lock file
After running the bundle install command, 'Gemfile.lock ' is created in the working directory. What do the directives inside that file mean?
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