Every implementation of the C++ Standard Library like one included to Embarcadero RAD Studio C++ compilers provides two ways for (pseudo-)random numbers generation: old-fashioned facilities from <cstdlib> and modern facilities provided by <random>.
Facilities from <cstdlib>
There are two very simple functions provided by the C random library: std::srand() and std::rand().
In addition to Helpers for Generic C++ Code Iterating Over Sequences the C++17 Standard Library provides the following helpers for writing generic code:
#include <iterator> // new helpers of C++17 are defined here
template<class Container>
void…
The iterator library that is part of the C++ Standard Library provides the following helpers for writing generic code:
#include <iterator> // helpers are defined here
template<class Container>
void foo(Container& c)
{
// Generic way to obtain (constant)…
Since C++11 there are elegant way to access each element of a containers (or, more generally, sequences) – so called range-for-statement. The syntaxes are follow:
template<class Container>
void foo(Container& container)
{
for (auto element : container); // (1)
for (const auto element : container); // (2)
for (auto& element : container); // (3)
for…
Let’s slightly modify the example from The Move Iterator Adapter in C++ post:
#include <algorithm>
#include <list>
#include <string>
#include <vector>
/// @warning BUG! PLEASE, DON'T USE!
auto deep_copy_to_list(const…
The dereference prefix operator * being applied to iterator returns the lvalue reference to the element pointed by the iterator. Therefore, algorithms such as std::copy or std::transform calls copying constructors of processed elements, for example:
#include…
By using bidirectional iterator or random access iterator (see Iterator Categories in C++) it’s possible to traverse the sequence in backward direction by using operator -- or by using the special adapter template class std::reverse_iterator. But why to bother with reverse iterators if the operator -- is available for iterators with bidirectional traversing capabilities? The answer is…
Conceptually, iterators are consists of five categories:
input iterator is intended to traverse sequences in the forward direction and provides the read access to the pointed sequence element;output iterator is intended to traverse sequences in the forward direction and…
Iterator abstracts the concept of pointer to the sequence in range [begin, end), and thus provides the following basic operations:
dereference to obtain the current element;movement to point the next element;comparison to determine at least the end of…
In programming, one of the most used variables is text strings, and they are sometimes really important when storing and retrieving valuable data. It is important to store your data safely in its language and localization. Most programming languages have issues when storing texts and letters. In C++, there is very old well-known string type (arrays of chars) and modern types…
