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Difference between size_t and std::size_t
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90
C's size_t and C++'s std::size_t are both same.
In C, it's defined in <stddef.h> and in ...
Java HashMap performance optimization / alternative
...ted out the hashCode() method was to blame. It was only generating around 20,000 codes for 26 million distinct objects. That is an average of 1,300 objects per hash bucket = very very bad. However if I turn the two arrays into a number in base 52 I am guaranteed to get a unique hash code for every o...
What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phon
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80
Well considering there's no overhead difference between a varchar(30) and a varchar(100) if you'...
How to git-svn clone the last n revisions from a Subversion repository?
... start your clone at ( -r$REV:HEAD).
For example: git svn clone -s -r1450:HEAD some/svn/repo
Git's data structure is based on pointers in a directed acyclic graph (DAG), which makes it trivial to walk back n commits. But in SVN ( and therefore in Git-SVN) you will have to find the revision num...
Clearing all cookies with JavaScript
...ookies() {
var cookies = document.cookie.split(";");
for (var i = 0; i < cookies.length; i++) {
var cookie = cookies[i];
var eqPos = cookie.indexOf("=");
var name = eqPos > -1 ? cookie.substr(0, eqPos) : cookie;
document.cookie = name + "=;expires=Thu, ...
How to force R to use a specified factor level as reference in a regression?
... the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor b in DF by use of th...
Does MySQL ignore null values on unique constraints?
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440
Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x I...
Difference between Array and List in scala
... |
edited Apr 26 '10 at 11:26
answered Apr 26 '10 at 11:17
...
How to sort with lambda in Python
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+200
Use
a = sorted(a, key=lambda x: x.modified, reverse=True)
# ^^^^
On Python 2.x, the sorted function takes its argument...
fatal: Not a valid object name: 'master'
...wered Feb 6 '12 at 15:19
user229044♦user229044
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