Talk:cpp/algorithm/is permutation

Added requirement that predicate be an equivalence relation. An example code for this is:

   #include <algorithm>
   #include <iostream>
   #include <vector>
   int main()
   {
       const auto p = [] (const auto lhs, const auto rhs) { return std::abs(lhs - rhs) < 2; };
       const std::vector<int> v0{1, 0}, v1{1, 2}, v0prime{0, 1};
       std::cout << "v0 is permutation of v1 w.r.t. predicate p: " << std::is_permutation(v0.cbegin(), v0.cend(), v1.cbegin(), v1.cend(), p) << '\n';
       std::cout << "v0prime is permutation of v1 w.r.t. predicate p: " << std::is_permutation(v0prime.cbegin(), v0prime.cend(), v1.cbegin(), v1.cend(), p) << '\n';
       return 0;
   }

80.147.162.235 22:39, 6 April 2017 (PDT)