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What are the applications of binary trees?
...oving from one level to the next requires one comparison, and there are log_2(m) levels, for a total of log_2(m) comparisons.
In contrast, an n-ary tree will require log_2(n) comparisons (using a binary search) to move to the next level. Since there are log_n(m) total levels, the search will requi...
Run a callback only if an attribute has changed in Rails
...
Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae...
In C#, should I use string.Empty or String.Empty or “” to intitialize a string?
...1
.locals init ([0] string test1,
[1] string test11)
IL_0000: nop
IL_0001: ldsfld string [mscorlib]System.String::Empty
IL_0006: stloc.0
IL_0007: ldloc.0
IL_0008: stloc.1
IL_0009: ret
} // end of method Form1::Test1
.method private hidebysig instance void ...
Can I have onScrollListener for a ScrollView?
...dited Sep 16 '16 at 6:48
Pavneet_Singh
33.3k55 gold badges3939 silver badges5757 bronze badges
answered Apr 29 '14 at 13:06
...
How can I extract the folder path from file path in Python?
....path.split(os.path.abspath(existGDBPath))
('T:\\Data\\DBDesign', 'DBDesign_93_v141b.mdb')
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Why do you need explicitly have the “self” argument in a Python method?
...hing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
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What really happens in a try { return x; } finally { x = null; } statement?
...ged
{
.maxstack 1
.locals init (
[0] int32 CS$1$0000)
L_0000: call int32 Program::SomeNumber()
L_0005: stloc.0
L_0006: leave.s L_000e
L_0008: call void Program::Foo()
L_000d: endfinally
L_000e: ldloc.0
L_000f: ret
.try L_0000 to L_0008 finally hand...
How to find the width of a div using vanilla JavaScript?
... edited Nov 4 '15 at 11:07
sudo_dudo
50744 silver badges1616 bronze badges
answered Sep 12 '14 at 18:10
user3...
Dynamic variable names in Bash
...ay, with command names as keys.
# Requires bash 4, though
declare -A magic_variable=()
function grep_search() {
magic_variable[$1]=$( ls | tail -1 )
echo ${magic_variable[$1]}
}
If you can't use associative arrays (e.g., you must support bash 3), you can use declare to create dynamic var...
How to resize superview to fit all subviews with autolayout?
... *) indexPath
{
static TSTableViewCell *sizingCell;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
sizingCell = (TSTableViewCell*)[tableView dequeueReusableCellWithIdentifier: @"TSTableViewCell"];
});
// configure the cell
sizingCell.text = self....