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How can I multiply and divide using only bit shifting and adding?
...ion)
(_2 means base 2)
As you can see, multiplication can be decomposed into adding and shifting and back again. This is also why multiplication takes longer than bit shifts or adding - it's O(n^2) rather than O(n) in the number of bits. Real computer systems (as opposed to theoretical computer s...
HTTPS connections over proxy servers
...can remember, you need to use a HTTP CONNECT query on the proxy. this will convert the request connection to a transparent TCP/IP tunnel.
so you need to know if the proxy server you use support this protocol.
share
...
How to suppress scientific notation when printing float values?
...o say, "you manage the display of precision yourself." The actual (Python internal) precision isn't changed, as is often done in other languages.
– JS.
Aug 22 '12 at 20:42
ad...
How to wait for 2 seconds?
...
--Example 2
DECLARE @Delay2 DATETIME
SELECT @Delay2 = dateadd(SECOND, 2, convert(DATETIME, 0))
WAITFOR DELAY @Delay2
A note on waiting for TIME vs DELAY:
Have you ever noticed that if you accidentally pass WAITFOR TIME a date that already passed, even by just a second, it will never return? Che...
MySQL JOIN the most recent row only?
... a synonym for INNER JOIN.
Test case:
CREATE TABLE customer (customer_id int);
CREATE TABLE customer_data (
id int,
customer_id int,
title varchar(10),
forename varchar(10),
surname varchar(10)
);
INSERT INTO customer VALUES (1);
INSERT INTO customer VALUES (2);
INSERT INTO custo...
Calling C/C++ from Python?
...
You should have a look at Boost.Python. Here is the short introduction taken from their website:
The Boost Python Library is a framework for interfacing Python and
C++. It allows you to quickly and seamlessly expose C++ classes
functions and objects to Python, and vice-versa...
Scala @ operator
...attern to a variable. Consider the following, for instance:
val o: Option[Int] = Some(2)
You can easily extract the content:
o match {
case Some(x) => println(x)
case None =>
}
But what if you wanted not the content of Some, but the option itself? That would be accomplished with this...
What is the best way to use a HashMap in C++?
...by the key, insert and access is in O(log n). Usually the standard library internally uses red black trees for ordered maps. But this is just an implementation detail. In an unordered map insert and access is in O(1). It is just another name for a hashtable.
An example with (ordered) std::map:
#in...
Why does Sql Server keep executing after raiserror when xact_abort is on?
..._id('tempdb..#RAISERRORS') is null)
create table #RAISERRORS (ErrorNumber int, ErrorMessage varchar(400), ErrorSeverity int, ErrorState int, ErrorLine int, ErrorProcedure varchar(128));
-- this will determine if the transaction level of the query to programatically determine if we need to begin a ...
how to implement a long click listener on a listview
... onItemLongClick(AdapterView<?> arg0, View arg1,
int pos, long id) {
// TODO Auto-generated method stub
Log.v("long clicked","pos: " + pos);
return true;
}
});
The XML for each item in the list (should...