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Comment by merlincorey | Hacker News Reader

Seems completely broken now; like others, I tried to test something, found I had to sign up, signed up, and found I have "0 free credits".

I really wanted to see what it was gonna do for Python -> C++ converting some nested dictionary and list comprehensions:

    def foobar(x, y):
      return {
        _: __
        for _, __ in zip(
          [_ for _ in x if _ in y],
          [_ for _ in x if _ not in y]
        )
      }
        
    {3: 1, 4: 2} == foobar([1, 2, 3, 4], [3, 4, 5, 6])

View on HN

I bought some credits. Here is the result (Python to C++):

  std::map<int, int> foobar(std::vector<int> x, std::vector<int> y) {
    std::map<int, int> map;

    for (int i = 0; i < x.size(); i++) {
      if (std::find(y.begin(), y.end(), x[i]) != y.end()) {
        map[x[i]] = x[i + 1];
      }
    }
    
    return map;
  }

Thanks for checking into that... doesn't look like the AI is even close to ready for prime time right now as this is not the correct translation:

    #include <algorithm>
    #include <iostream>
    #include <map>
    #include <vector>

    std::map<int, int> foobar(std::vector<int> x, std::vector<int> y) {
      std::map<int, int> map;

      for (int i = 0; i < x.size(); i++) {
        if (std::find(y.begin(), y.end(), x[i]) != y.end()) {
          map[x[i]] = x[i + 1];
        }
      }

      return map;
    }

    int main(int argc, char** argv) {
      std::vector<int> ex{ 1, 2, 3, 4 };
      std::vector<int> wy{ 3, 4, 5, 6 };
      std::map<int, int> result = foobar(ex, wy);

      std::cout << "{";
      for ( const auto &item : result) {
        std::cout << item.first << ": " << item.second << ", ";
      }
      std::cout << "}" << std::endl;
    }

It outputs:

    {3: 4, 4: 0, }

But it SHOULD be getting:

    {3: 1, 4: 2, }

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