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What is better, adjacency lists or adjacency matrices for graph problems in C++?
...e of a specific edge
between any two nodes O(1)
It is slow to iterate over all edges
It is slow to add/delete a node; a complex operation O(n^2)
It is fast to add a new edge O(1)
Adjacency List
Memory usage depends on the number of edges (not number of nodes),
which might save a lot of memor...
Use jQuery to change an HTML tag?
...
Here's an extension that will do it all, on as many elements in as many ways...
Example usage:
keep existing class and attributes:
$('div#change').replaceTag('<span>', true);
or
Discard existing class and attributes:
...
How to take all but the last element in a sequence using LINQ?
... using generators (yield return).
public static IEnumerable<T> TakeAllButLast<T>(this IEnumerable<T> source) {
var it = source.GetEnumerator();
bool hasRemainingItems = false;
bool isFirst = true;
T item = default(T);
do {
hasRemainingItems = it.MoveN...
Get an object properties list in Objective-C
...turn nil;
}
NSMutableDictionary *results = [[[NSMutableDictionary alloc] init] autorelease];
unsigned int outCount, i;
objc_property_t *properties = class_copyPropertyList(klass, &outCount);
for (i = 0; i < outCount; i++) {
objc_property_t property = properties[i...
SQL-Server: Error - Exclusive access could not be obtained because the database is in use
I am actually trying to make a script (in Sql Server 2008) to restore one database from one backup file. I made the following code and I am getting an error -
...
Set every cell in matrix to 0 if that row or column contains a 0
Given a NxN matrix with 0s and 1s. Set every row that contains a 0 to all 0 s and set every column that contains a 0 to all 0 s.
...
What's the difference between IQueryable and IEnumerable
...;>), which can be thought of as "is the 'Age' property > 18".
This allows things like LINQ-to-SQL to exist because they can parse the expression tree and convert it into equivalent SQL. And because the provider doesn't need to execute until the IQueryable is enumerated (it implements IEnum...
Why can't I reference my class library?
... Then Microsoft should say this and include an option to put them all at the same version.
– PRMan
Apr 30 '17 at 23:12
1
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The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communicat
What is this error all about, and how would I go about solving it?
14 Answers
14
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JPA and Hibernate - Criteria vs. JPQL or HQL
...dynamic queries. For example it is much easier to add some ordering dynamically or leave some parts (e.g. restrictions) out depending on some parameter.
On the other hand I'm using HQL for static and complex queries, because it's much easier to understand/read HQL. Also, HQL is a bit more powerful...