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How can two strings be concatenated?
...osters pointed out, paste can do two things:
concatenate values into one "string", e.g.
> paste("Hello", "world", sep=" ")
[1] "Hello world"
where the argument sep specifies the character(s) to be used between the arguments to concatenate,
or collapse character vectors
> x <- c("Hello"...
What's the difference between SoftReference and WeakReference in Java?
...ort java.util.HashMap;
public class Test {
public static void main(String args[]) {
HashMap<Employee, EmployeeVal> aMap = new
HashMap<Employee, EmployeeVal>();
Employee emp = new Employee("Vinoth");
EmployeeVal val = new EmployeeVa...
Red black tree over avl tree
...ack tree.
AVL trees store the balance factor at each node. This takes O(N) extra space. However, if we know that the keys that will be inserted in the tree will always be greater than zero, we can use the sign bit of the keys to store the colour information of a red-black tree. Thus, in such cases r...
Correct way to load a Nib for a UIView subclass
...sult = nil;
NSArray* elements = [[NSBundle mainBundle] loadNibNamed: NSStringFromClass([self class]) owner:self options: nil];
for (id anObject in elements)
{
if ([anObject isKindOfClass:[self class]])
{
result = anObject;
break;
}
}
...
Map implementation with duplicate keys
...ions external library. You can simply implement the following Map:
Map<String, ArrayList<String>> hashMap = new HashMap<String, ArrayList>();
public static void main(String... arg) {
// Add data with duplicate keys
addValues("A", "a1");
addValues("A", "a2");
addValues...
Select columns from result set of stored procedure
...UERY over OPENROWSET, given that OPENQUERY does not require the connection-string definition within the proc.
Note 2:
Having said all this: normally I would just use INSERT ... EXEC :) Yes, it's 10 mins extra typing, but if I can help it, I prefer not to jigger around with:
(a) quotes within qu...
Emulate a do-while loop in Python?
...lso, is this real code where you are processing comments? What if you have strings with slashes? ie: print "blah // <-- does that mess you up?"
– Tom
Apr 13 '09 at 7:44
4
...
Case insensitive 'in'
...pper() for name in USERNAMES) would create only a generator and one needed string at a time - massive memory savings if you're doing this operation a lot. (even more savings, if you simply create a list of lowercase usernames that you reuse for checking every time)
– viraptor
...
Is it better to call ToList() or ToArray() in LINQ queries?
...EDIT
A couple of people have asked me about the consequence of having the extra unused memory in the List<T> value.
This is a valid concern. If the created collection is long lived, is never modified after being created and has a high chance of landing in the Gen2 heap then you may be bet...
is vs typeof
... +1: In the past I wondered why the C# compiler didn't compile typeof(string).TypeHandle to the ldtoken CIL instruction, but it looks like the CLR takes care of it in the JIT. It still takes a few extra opcodes but it's a more generalized application of the optimization.
–...