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Way to go from recursion to iteration
... you have more than one recursive call inside and you want to preserve the order of the calls, you have to add them in the reverse order to the stack:
foo(first);
foo(second);
has to be replaced by
stack.push(second);
stack.push(first);
Edit: The article Stacks and Recursion Elimination (or Articl...
How to sort a file, based on its numerical values for a field?
...614990234375
-0.907928466796875
1.135406494140625
Which is obviously not ordered by numeric value.
Then, I guess that a more precise answer would be to use sort -n but only if all the values are positive.
P.S.: Using sort -g returns just the same results for this example
Edit:
Looks like the l...
Advantages of std::for_each over for loop
..._each could be useful, especially if you have several functions to call in order but need to run each method for all objects before next... but maybe that's just me. ;)
Update 2: I've written my own one-liner wrappers of stl-algos that work with ranges instead of pair of iterators. boost::range_ex, ...
Biggest GWT Pitfalls? [closed]
...s your data back and forth via the RPC mechanism.
Problem: Sometimes in order to populate your GWT page, you need to make a server call when the page first loads. It can be annoying for the user to sit there and watch a loading symbol while you fetch the data you need.
Solution: In the case of a...
SQL JOIN and different types of JOINs
... a.actor_id -- JOIN predicate with the outer query!
GROUP BY f.film_id
ORDER BY revenue DESC
LIMIT 5
) AS f
ON true
It will find the TOP 5 revenue producing films per actor. Every time you need a TOP-N-per-something query, LATERAL JOIN will be your friend. If you're a SQL Server person, then...
What is a mixin, and why are they useful?
...
This particular example could have been achieved via the functools.total_ordering() decorator, but the game here was to reinvent the wheel:
import functools
@functools.total_ordering
class Integer(object):
def __init__(self, i):
self.i = i
def __le__(self, other):
return s...
Closing Database Connections in Java
...nnection, you need to explicitly close it by calling its close() method in order to release any other database resources (cursors, handles, etc) the connection may be holding on to.
Actually, the safe pattern in Java is to close your ResultSet, Statement, and Connection (in that order) in a finall...
Java ArrayList - how can I tell if two lists are equal, order not mattering?
...ighly better solution is to first check if they are the same length before ordering, if they are not, then they are not equal, then sort, then use equals. For example if you had two lists of Strings it would be something like:
public boolean equalLists(List<String> one, List<String> tw...
Explanation of the UML arrows
...ice reference but to me a Menu -> MenuItem has the same relation like a Order -> OrderItem so both of them are Compositions.
– Ignacio Soler Garcia
Jun 28 '13 at 10:53
4
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SQL Server: Difference between PARTITION BY and GROUP BY
... group by modifies the entire query, like:
select customerId, count(*) as orderCount
from Orders
group by customerId
But partition by just works on a window function, like row_number:
select row_number() over (partition by customerId order by orderId)
as OrderNumberForThisCustomer
from Order...