// See www.openfst.org for extensive documentation on this weighted
  // finite-state transducer library.
  //
  // Prints out various information about a PDT such as number of states, arcs,
  // and parentheses.
  
  #include <cstring>
  
  #include <memory>
  #include <string>
  #include <vector>
  
  #include <fst/flags.h>
  #include <fst/log.h>
  
  #include <fst/extensions/pdt/pdtscript.h>
  #include <fst/util.h>
  
  DEFINE_string(pdt_parentheses, "", "PDT parenthesis label pairs");
  
  int main(int argc, char **argv) {
    namespace s = fst::script;
    using fst::ReadLabelPairs;
    using fst::script::FstClass;
  
    string usage = "Prints out information about a PDT.
  
    Usage: ";
    usage += argv[0];
    usage += " in.pdt
  ";
  
    std::set_new_handler(FailedNewHandler);
    SET_FLAGS(usage.c_str(), &argc, &argv, true);
    if (argc > 2) {
      ShowUsage();
      return 1;
    }
  
    const string in_name =
        (argc > 1 && (strcmp(argv[1], "-") != 0)) ? argv[1] : "";
  
    std::unique_ptr<FstClass> ifst(FstClass::Read(in_name));
    if (!ifst) return 1;
  
    if (FLAGS_pdt_parentheses.empty()) {
      LOG(ERROR) << argv[0] << ": No PDT parenthesis label pairs provided";
      return 1;
    }
  
    std::vector<s::LabelPair> parens;
    if (!ReadLabelPairs(FLAGS_pdt_parentheses, &parens, false)) return 1;
  
    s::PrintPdtInfo(*ifst, parens);
  
    return 0;
  }