Permutation.h

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/* Author: Mark Moll */
 
#ifndef OMPL_DATASTRUCTURES_PERMUTATION_
#define OMPL_DATASTRUCTURES_PERMUTATION_
 
#include <random>
 
namespace ompl
{
    class Permutation : public std::vector<int>
    {
    public:
        Permutation(std::size_t n) : std::vector<int>(n)
        {
            permute(n);
        }
        void permute(unsigned int n)
        {
            if (size() < n)
                resize(n);
            for (unsigned int i = 0; i < n; ++i)
                operator[](i) = i;
            std::shuffle(begin(), begin() + n, generator_);
        }
 
    private:
        std::mt19937 generator_;
    };
}
 
#endif