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Simple regular expression for a decimal with a precision of 2
...t:
\d+(\.\d{1,2})?
Both assume that both have at least one digit before and one after the decimal place.
To require that the whole string is a number of this form, wrap the expression in start and end tags such as (in Perl's form):
^\d+(\.\d{1,2})?$
To match numbers without a leading digit be...
How to reverse a singly linked list using only two pointers?
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Any alternative? No, this is as simple as it gets, and there's no fundamentally-different way of doing it. This algorithm is already O(n) time, and you can't get any faster than that, as you must modify every node.
It looks like your code is on the right track, but it's not...
Why does an NSInteger variable have to be cast to long when used as a format argument?
...le on OS X (64-bit), because on that platform NSInteger is defined as long and is a 64-bit integer. The %i format, on the other hand, is for int, which is 32-bit. So the format and the actual parameter do not match in size.
Since NSInteger is 32-bit or 64-bit, depending on the platform, the compile...
How can I get a view's current width and height when using autolayout constraints?
...tion, or in response to an event). Is there a way to get its current width and height?
5 Answers
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Formatting Decimal places in R
...number of decimal places are displayed. This is often done for consistency and standardisation purposes rather than being concerned with significant figures.
Solution:
The following code shows exactly two decimal places for the number x.
format(round(x, 2), nsmall = 2)
For example:
format(roun...
PHP cURL vs file_get_contents
...ests where the header, HTTP request method, timeout, cookiejar, redirects, and other important things do not matter.
fopen() with a stream context or cURL with setopt are powerdrills with every bit and option you can think of.
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Activity transition in Android
How can I define the transition between two activities for Android 1.5 and later?
I would like an activity to fade in.
14 ...
API Versioning for Rails Routes
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The original form of this answer is wildly different, and can be found here. Just proof that there's more than one way to skin a cat.
I've updated the answer since to use namespaces and to use 301 redirects -- rather than the default of 302. Thanks to pixeltrix and Bo Jeanes fo...
MySQL Data - Best way to implement paging?
...ments, the first argument specifies the offset of the first row to return, and the second specifies the maximum number of rows to return. The offset of the initial row is 0 (not 1):
SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15
To retrieve all rows from a certain offset up to the end of the r...
Pad a number with leading zeros in JavaScript [duplicate]
...ements. " - I don't think that's correct. It just sets the length property and join iterates length times. Access of an undefined property always returns undefined. See "5" in Array(5) vs "0" in [1]
– Benjamin Gruenbaum
Jul 24 '14 at 11:56
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