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How to increment a pointer address and pointer's value?
...str)
{
cout<<*str<<endl; // printing the string
*str++; // incrementing the address(pointer)
// check above about the prcedence and associativity
}
free(str[0]);
free(str[1]);
fr...
General guidelines to avoid memory leaks in C++ [closed]
...e heap internally (note the double negation... :-) ...). For example, std::string implemented with Small String Optimization will have a buffer "on the stack of the class" for small strings (~15 chars), and will use a pointer to a memory in the heap for larger strings... But from the outside, std::s...
Mapping many-to-many association table with extra column(s)
...ments java.io.Serializable{
private ACId id = new ACId();
private String extra;
public AC(){
}
public ACId getId() {
return id;
}
public void setId(ACId id) {
this.id = id;
}
public A getA(){
return getId().getA();
}
public C...
Grep characters before and after match?
...
3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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What does “fragment” mean in ANTLR?
...lly they'll improve readability of your grammars.
look at this example :
STRING : '"' (ESC | ~["\\])* '"' ;
fragment ESC : '\\' (["\\/bfnrt] | UNICODE) ;
fragment UNICODE : 'u' HEX HEX HEX HEX ;
fragment HEX : [0-9a-fA-F] ;
STRING is a lexer using fragment rule like ESC .Unicode is used in Esc r...
How important is the order of columns in indexes?
...mns involved.
Giving that rationale, the only difference is comparing two 'strings' that differ earlier versus later in the string. This is a tiny part of the total cost. There is no "first pass / second pass", as mentioned in one Answer.
So, what order should be used?
Start with column(s) tested...
What does the `forall` keyword in Haskell/GHC do?
... b)
ghci> liftTup (\x -> [x]) (5, "Hello")
No instance for (Num [Char])
...
ghci> -- huh?
ghci> :t liftTup
liftTup :: (t -> t1) -> (t, t) -> (t1, t1)
"Hmm.. why does GHC infer that the tuple must contain two of the same type? Let's tell it they don't have to be"
-- te...
Removing an element from an Array (Java) [duplicate]
...ur own answer, I can tell better what you are trying to do:
public static String[] removeElements(String[] input, String deleteMe) {
List result = new LinkedList();
for(String item : input)
if(!deleteMe.equals(item))
result.add(item);
return result.toArray(input);
...
What are copy elision and return value optimization?
....
Copy elision is an optimization implemented by most compilers to prevent extra (potentially expensive) copies in certain situations. It makes returning by value or pass-by-value feasible in practice (restrictions apply).
It's the only form of optimization that elides (ha!) the as-if rule - copy el...
Android Reading from an Input stream efficiently
...
The problem in your code is that it's creating lots of heavy String objects, copying their contents and performing operations on them. Instead, you should use StringBuilder to avoid creating new String objects on each append and to avoid copying the char arrays. The implementation for ...