// Using C++ Standard Library algorithm next_permutation
//
#include <iostream>
#include <vector>
#include <algorithm>
#include <iterator>

namespace my {
  template<typename T>
  struct State{
    T i;
    std::vector<T> v;
    State(T ind,std::vector<T> vec) {i=ind; v=std::move(vec);} 
    void print(){
      std::cout<<"state # "<<i<<" ( ";
      for(auto x:v) std::cout<<x<<" ";
      std::cout<<")"<<std::endl;
    }
  };
}

int main () {
  std::vector<my::State<int>> states;
  std::vector<int> vec={0,1,2,3,4};
  std::sort(vec.begin(),vec.end()); // make sure next_permutation starts ok
  int i = 1;
  do {
    states.push_back(my::State(i,vec));
    i++;
  } while (next_permutation (vec.begin(),vec.end()));
  for (auto s:states) s.print();
}
// state # 1 ( 0 1 2 3 4 )
// ...
// state # 120 ( 4 3 2 1 0 )