Computer Programming

A profiler examines source code or machine code to determine memory and performance complexities, usage of certain instructions and the frequency and duration of function calls. Profilers are used as an aid to optimising code during the performance engineering phase of development.

A compiler processes source code to produce machine code. A compiler also optimises the emitted code through inline expansion, compile-time computations, tail-call recursions, code re-ordering and so on. Compiler optimisations are well-defined, but the analysis is primitive compared to profiling which performs more extensive and time-consuming analysis of the code.

yes

In C++, the const modifier makes a reference a constant reference.

int i = 42;

const int& r = i;

In the above example, both r and i refer to the same object: a primitive integral with the value 42. That is, r is an alias for i; they are one and the same object. However, the reference r is declared constant so we cannot change the object it refers to by assigning a new value to it. But we can assign a new value to i. And since r and i are the same object, the value of r also changes, despite being decalred constant.

Normally you would not use a constant reference to refer to a local object, since the constness of the reference cannot be guaranteed. However, when we pass an object to a function that expects a constant reference to an object, we give a gurantee to the caller that the object's immutable members will not be changed by the function. This is because the function only has access to the object through the constant reference (formal argument), not the reference we actually passed (actual argument). Therefore it only has access to the constant member functions.

Note that mutable members are nonstatic members that are declared mutable. Typically these will be declared private, for internal use only, such as counters or iterators. As such, modifying a mutable member does not alter an object's external state, as defined by its immutable members. This allows us to invoke constant member functions, which assures us that the object's external state remains unchanged, regardless of the internal state.

Mutable members can also be used to enable lazy construction. That is, an accessor initialises a complex embedded member object when it is first accessed, rather than during construction. This allows the containing object to be constructed much faster, provided the accessor is not invoked as part of the construction process of course. In order for this to work, the embedded member must be a mutable pointer that is initially NULL. When the accessor is invoked for the first time, the complex member is constructed and assigned to the NULL pointer which is then returned (usually by constant reference, but not always). Thereafter, the pointer is no longer NULL and can simply be returned on subsequent accesses. The main advantage of lazy construction is that if the accessor is never called before the containing object falls from scope, we don't waste time and memory constructing an embedded object that was never actually required (and if we had a thousand containing objects, we'd be constructing a thousand embedded objects for no good reason). However, all accessors must be declared constant as they must be accessible to all other member functions, including constant member functions. If the member were not mutable, lazy construction of that member becomes impossible.

You pop up pirate

Environment variables are a set of dynamic values that can

affect the way running processes will behave on a computer.

Global Variables

Or: variables with names longer than 128 characters.

If the variable is local to the function it exists until the function returns.

i appose this is the wrong answer

The Main method is the method in which execution to any java program begins.

A main method declaration looks as follows:

public static void main(String args[]){

}

The method is public because it be accessible to the JVM to begin execution of the program.

It is Static because it be available for execution without an object instance. you may know that you need an object instance to invoke any method. So you cannot begin execution of a class without its object if the main method was not static.

It returns only a void because, once the main method execution is over, the program terminates. So there can be no data that can be returned by the Main method

The last parameter is String args[]. This is used to signify that the user may opt to enter parameters to the java program at command line. We can use both String[] args or String args[]. The Java compiler would accept both forms.

The tilde symbol in a web address (eg. http://www.website.com/~tim) usually means that the website belongs to the user with the name after the tilde (in this example, the username is "tim")

Increment or decrement the pointer by the required offset.

A buffer overflow occurs when a program tries to store some amount of data in a location which cannot contain that amount of data. For example, trying to store an array of 10 integers in an array with room for 5 integers will cause a buffer overflow.

Buffer overflows are common in C/C++, specifically in the strcpy function. This function copies the data from one string (char array) into another. It is often abused by clever hackers to either crash a program or to inject their own instructions onto the execution stack.

The "extra" data copied over from the larger array doesn't magically disappear. The "overflow" refers to that data overwriting data on the stack. While this will often just crash the program (or computer), those clever hackers mentioned above may happen to know enough about the program structure to be able to insert their own low-level computer instructions to execute arbitrary code on the machine.

Each object should be responsible for its own logic and data, and so each object's tests should be responsible for its own tests. The top-down approach is the polar opposite of this design, as the top level object would be responsible for testing all of its enclosed objects. This works well in procedural programming, but explicitly violates the concepts of object oriented programming, which states that no object should be concerned about the details of any other object's internal design.

I dont know it.

Depends on the programming language, some languages may have already initialize an array with null (or the default value of the type), some of them require explicitly assignments by stepping through each element of that array, and assigning them with null. (imperative languages)

the phenomenon of obtaining a degenerate basic feasible solution in a linear programming problem known as degeneracy.

There is no best, worst or average case running time for bucket sort. We must assume that the number of elements in the list is comparable to the possible number of values in the list. Making it O(n).

Correct me if I am wrong but if the values in the list are already sorted or close to being already sorted it would be O(n lg n).

Both base 16 and base 2 number systems use binary numbers (1 and 0) to write out and define decimal numbers.

Support classification information systems are transaction processing systems, management information systems, knowledge management systems, office automation systems, decision support systems, group support systems.

The Sort dialog box available from the Data menu item,

10 nanofarad

12

define program

i. program means set of instruction which are required for a particular type of task is called program

ii. set of instruction or commands which are given for the computer to do different activity or jobs or works is called program

define programming

the process of creating/modifying a program; some people's job, others' hobby

It means Terminate-Stay-Resident. A TSR is a program that remains in memory when the program ends.