#include <iostream>
#include <random>
#include <vector>
 
int main()
{
   std::vector<double> weights{0.0, 1.0, 2.0};
   std::size_t i(0);
   std::discrete_distribution<> dist(weights.size(), weights.front(), weights.back(), [&weights, &i](double)
   {
      auto w = weights[i];
      ++i;
      return w;
   });
   std::discrete_distribution<> dist2(weights.cbegin(), weights.cend());
   for ( const auto& entry : dist.probabilities() )
   {
      std::cerr << entry << " ";
   }
   std::cerr << "\n";
   for ( const auto& entry : dist2.probabilities() )
   {
      std::cerr << entry << " ";
   }
   std::cerr << "\n";
}

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