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Is there an advantage to use a Synchronized Method instead of a Synchronized Block?
...
I know this is an old question but synchronizing on "this" is considered in some circles to be an anti-pattern. The unintended consequence is that outside of the class someone can lock on an object reference that is equal to "this" and prevent ot...
When to use a linked list over an array/array list?
...t to be able to insert items in the middle of the list (such as a priority queue)
Arrays are preferable when:
you need indexed/random access to elements
you know the number of elements in the array ahead of time so that you can allocate the correct amount of memory for the array
you need speed ...
What is this 'Lambda' everyone keeps speaking of?
...ent, index) {
// do something useful with element
// element is the equivalent of array[i] from above
});
The above abstraction may not be that useful, but there are other higher order functions, like forEach, that perform much more useful tasks. For example filter:
var numbers = [1, 2, 3, ...
Is it possible to make abstract classes in Python?
...ompiler/interpret know that all the methods are from the abstract class in question?
– Charlie Parker
Mar 17 '14 at 3:30
35
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Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
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See the C FAQ, Question 1.32
Q: What is the difference between these initializations?
char a[] = "string literal";
char *p = "string literal";
My program crashes if I try to assign a new value to p[i].
A: A string literal...
How to check if a map contains a key in Go?
...
@Mheni, I know I'm a bit late here, but this question discusses the lookup complexity in go. Most of the time the amortized complexity is O(1) but it's worth reading the answers on that question.
– 3ocene
Oct 9 '18 at 20:50
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What do 3 dots next to a parameter type mean in Java?
...trings){
// do what ever you want
}
// the code above is equivalent to
for( int i = 0; i < strings.length; i++){
// classical for. In this case you use strings[i]
}
}
This answer borrows heavily from kiswa's and Lorenzo's... and also from Graphain's comment.
...
What are the options for storing hierarchical data in a relational database? [closed]
...d. Use an Adjacency List to maintain the hierarchy and use Nested Sets to query the hierarchy.
The problem up until now has been that the coversion method from an Adjacecy List to Nested Sets has been frightfully slow because most people use the extreme RBAR method known as a "Push Stack" to do th...
What are bitwise operators?
... several cases.
x << y
is the same as
x * 2y
if you need to quickly multiply by a power of two, but watch out for shifting a 1-bit into the top bit - this makes the number negative unless it's unsigned. It's also useful when dealing with different sizes of data. For example, reading...
How do you get the list of targets in a makefile?
...al order - i.e.: invoke as make list:
.PHONY: list
list:
@$(MAKE) -pRrq -f $(lastword $(MAKEFILE_LIST)) : 2>/dev/null | awk -v RS= -F: '/^# File/,/^# Finished Make data base/ {if ($$1 !~ "^[#.]") {print $$1}}' | sort | egrep -v -e '^[^[:alnum:]]' -e '^$@$$'
Important: On pasting this, make...