__random_sample() [1/2]

template<typename _InputIterator, typename _RandomAccessIterator, typename _RandomNumberGenerator, typename _Distance>

_RandomAccessIterator __gnu_cxx::__random_sample	(	_InputIterator	__first,
		_InputIterator	__last,
		_RandomAccessIterator	__out,
		_RandomNumberGenerator &	__rand,
		const _Distance	__n )

Definition at line 353 of file ext/algorithm.

    {
      // concept requirements
      __glibcxx_function_requires(_UnaryFunctionConcept<
          _RandomNumberGenerator, _Distance, _Distance>)
 
      _Distance __m = 0;
      _Distance __t = __n;
      for ( ; __first != __last && __m < __n; ++__m, ++__first)
      __out[__m] = *__first;
 
      while (__first != __last)
      {
        ++__t;
        _Distance __M = __rand(__t);
        if (__M < __n)
          __out[__M] = *__first;
        ++__first;
      }
      return __out + __m;
    }

References __glibcxx_function_requires.