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An iterator pattern provides a simple method for selecting, sequentially, the next item in a collection. Fixed Collection class BeverageForPizza { constructor(preferenceRank) { this.beverageList = beverageList; this.pointer = 0; } next() { return this.be...

The pattern (p1, p2) is strict in the outermost tuple constructor, which can lead to unexpected strictness behaviour. For example, the following expression diverges (using Data.Function.fix): fix $ \(x, y) -> (1, 2) since the match on (x, y) is strict in the tuple constructor. However, the fo...

int i; int n = 1000000; double area = 0; double h = 1.0 / n; #pragma omp parallel shared(n, h) { double thread_area = 0; // Private / local variable #pragma omp for for (i = 1; i <= n; i++) { double x = h * (i - 0.5); thread_area += (4.0 / (1.0 ...

double area; double h = 1.0 / n; #pragma omp parallel for shared(n, h, area) for (i = 1; i <= n; i++) { double x = h * (i - 0.5); #pragma atomic area += (4.0 / (1.0 + x*x)); } pi = h * area; In this example, each threads execute a subset of the iteration count and they accumula...

double area; double h = 1.0 / n; #pragma omp parallel for shared(n, h, area) for (i = 1; i <= n; i++) { double x = h * (i - 0.5); #pragma omp critical { area += (4.0 / (1.0 + x*x)); } } double pi = h * area; In this example, each threads execute a subset of the iteratio...

int i; int n = 1000000; double area = 0; double h = 1.0 / n; #pragma omp parallel for shared(n, h) reduction(+:area) for (i = 1; i <= n; i++) { double x = h * (i - 0.5); area += (4.0 / (1.0 + x*x)); } pi = h * area; In this example, each threads execute a subset of the iteration...

Include using System.Numerics and add a reference to System.Numerics to the project. using System; using System.Numerics; namespace Euler_25 { class Program { static void Main(string[] args) { BigInteger l1 = 1; BigInteger l2 = 1; ...

RAISERROR function will generate error in the TRY CATCH block: DECLARE @msg nvarchar(50) = 'Here is a problem!' BEGIN TRY print 'First statement'; RAISERROR(@msg, 11, 1); print 'Second statement'; END TRY BEGIN CATCH print 'Error: ' + ERROR_MESSAGE(); END CATCH RAISERROR ...

RAISERROR with severity (second parameter) less or equal to 10 will not throw exception. BEGIN TRY print 'First statement'; RAISERROR( 'Here is a problem!', 10, 15); print 'Second statement'; END TRY BEGIN CATCH print 'Error: ' + ERROR_MESSAGE(); END CATCH After RAISER...

You can re-throw error that you catch in CATCH block using TRHOW statement: DECLARE @msg nvarchar(50) = 'Here is a problem! Area: ''%s'' Line:''%i''' BEGIN TRY print 'First statement'; RAISERROR(@msg, 11, 1, 'TRY BLOCK', 2); print 'Second statement'; END TRY BEGIN CATCH print...

You can throw exception in try catch block: DECLARE @msg nvarchar(50) = 'Here is a problem!' BEGIN TRY print 'First statement'; THROW 51000, @msg, 15; print 'Second statement'; END TRY BEGIN CATCH print 'Error: ' + ERROR_MESSAGE(); THROW; END CATCH Exception with be ...

The following example code is slower than it needs to be : Map<String, String> map = new HashMap<>(); for (String key : map.keySet()) { String value = map.get(key); // Do something with key and value } That is because it requires a map lookup (the get() method) for each ...

Let's say you have a library that returns callbacks, for example the fs module in NodeJS: const fs = require("fs"); fs.readFile("/foo.txt", (err, data) => { if(err) throw err; console.log(data); }); We want to convert it to a promise returning API, with bluebird - ...

Ω-notation is used for asymptotic lower bound. Formal definition Let f(n) and g(n) be two functions defined on the set of the positive real numbers. We write f(n) = Ω(g(n)) if there are positive constants c and n0 such that: 0 ≤ c g(n) ≤ f(n) for all n ≥ n0. Notes f(n) = Ω(g(n)) means that f(n)...

Let f(n) and g(n) be two functions defined on the set of the positive real numbers, c, c1, c2, n0 are positive real constants. Notationf(n) = O(g(n))f(n) = Ω(g(n))f(n) = Θ(g(n))f(n) = o(g(n))f(n) = ω(g(n))Formal definition∃ c > 0, ∃ n0 > 0 : ∀ n ≥ n0, 0 ≤ f(n) ≤ c g(n)∃ c > 0, ∃ n0 > 0 ...

The PHP community has a lot of developers creating lots of code. This means that one library’s PHP code may use the same class name as another library. When both libraries are used in the same namespace, they collide and cause trouble. Namespaces solve this problem. As described in the PHP referenc...

to check if the given path exists path = '/home/john/temp' os.path.exists(path) #this returns false if path doesn't exist or if the path is a broken symbolic link

to check if the given path is a directory dirname = '/home/john/python' os.path.isdir(dirname) to check if the given path is a file filename = dirname + 'main.py' os.path.isfile(filename) to check if the given path is symbolic link symlink = dirname + 'some_sym_link' os.path.islink(symli...

A class or struct can have member functions as well as member variables. These functions have syntax mostly similar to standalone functions, and can be defined either inside or outside the class definition; if defined outside the class definition, the function's name is prefixed with the class' nam...

A common use of member functions is for encapsulation, using an accessor (commonly known as a getter) and a mutator (commonly known as a setter) instead of accessing fields directly. class Encapsulator { int encapsulated; public: int get_encapsulated() const { return encapsulated; }...