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Showing content from https://cplusplus.com/reference/algorithm/random_shuffle/ below:

function template

<algorithm>

template <class RandomAccessIterator>  void random_shuffle (RandomAccessIterator first, RandomAccessIterator last);

template <class RandomAccessIterator, class RandomNumberGenerator>  void random_shuffle (RandomAccessIterator first, RandomAccessIterator last,                       RandomNumberGenerator& gen);

template <class RandomAccessIterator>  void random_shuffle (RandomAccessIterator first, RandomAccessIterator last);

template <class RandomAccessIterator, class RandomNumberGenerator>  void random_shuffle (RandomAccessIterator first, RandomAccessIterator last,                       RandomNumberGenerator&& gen);

Randomly rearrange elements in range

The function swaps the value of each element with that of some other randomly picked element. When provided, the function gen determines which element is picked in every case. Otherwise, the function uses some unspecified source of randomness.

To specify a uniform random generator as those defined in <random>, see shuffle.

The behavior of this function template (2) is equivalent to:

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template <class RandomAccessIterator, class RandomNumberGenerator>
  void random_shuffle (RandomAccessIterator first, RandomAccessIterator last,
                       RandomNumberGenerator& gen)
{
  iterator_traits<RandomAccessIterator>::difference_type i, n;
  n = (last-first);
  for (i=n-1; i>0; --i) {
    swap (first[i],first[gen(i+1)]);
  }
}

first, last

Random-access iterators to the initial and final positions of the sequence to be shuffled. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.

gen

Unary function taking one argument and returning a value, both convertible to/from the appropriate difference type used by the iterators. The function shall return a non-negative value less than its argument.
This can either be a function pointer or a function object.

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// random_shuffle example
#include <iostream>     // std::cout
#include <algorithm>    // std::random_shuffle
#include <vector>       // std::vector
#include <ctime>        // std::time
#include <cstdlib>      // std::rand, std::srand

// random generator function:
int myrandom (int i) { return std::rand()%i;}

int main () {
  std::srand ( unsigned ( std::time(0) ) );
  std::vector<int> myvector;

  // set some values:
  for (int i=1; i<10; ++i) myvector.push_back(i); // 1 2 3 4 5 6 7 8 9

  // using built-in random generator:
  std::random_shuffle ( myvector.begin(), myvector.end() );

  // using myrandom:
  std::random_shuffle ( myvector.begin(), myvector.end(), myrandom);

  // print out content:
  std::cout << "myvector contains:";
  for (std::vector<int>::iterator it=myvector.begin(); it!=myvector.end(); ++it)
    std::cout << ' ' << *it;

  std::cout << '\n';

  return 0;
}

myvector contains: 3 4 1 6 8 9 2 7 5

rotate

Rotate left the elements in range (function template)

reverse

Reverse range (function template)

generate

Generate values for range with function (function template)

swap

Exchange values of two objects (function template)

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