DHT for Karim

dht.cc

#include <stdint.h>
#include <utility>
#include <iostream>
#include <google/dense_hash_map>

class mLong {
private:
  int64_t value; 
public: 
  mLong():
  value(0)
  {}

  mLong(const int64_t value):
  value(value)
  {}
  
  int64_t getValue(){
    return value;
  }
  
  inline bool operator() (const mLong& lhs, const mLong &rhs) const { 
    // Uncomment to see when used
    // std::cout << "Equality function called" << std::endl;
    return (lhs.value==rhs.value);
  }
  
  inline size_t operator() (const mLong& v) const {
    // Uncomment to see when used
    // std::cout << "Hash function called" << std::endl;
    return (size_t)v.value;
  }
};

template<class K>
class DHT {
  typedef google::dense_hash_map<K,int64_t,K,K> map_t;
  typedef typename map_t::iterator iterator_t;

  map_t local_dht;

public:
  DHT()
  {
    local_dht.set_empty_key(NULL);
  }

  bool insert(K e1, int v1) {
    return local_dht.insert(std::make_pair(e1, v1)).second;
  }

  int64_t retrieve(K e1)
  {     
    iterator_t element_itr = local_dht.find(e1);
    return (element_itr == local_dht.end())?-1:element_itr->second;
  }
};

int main(int argc, char** argv) {
 DHT<mLong> test;
 std::cout << ((test.insert(mLong(12),1)==true)?"PASS":"FAIL") << std::endl;
 std::cout << ((test.insert(mLong(14),5)==true)?"PASS":"FAIL") << std::endl;
 std::cout << ((test.insert(mLong(12),1)==false)?"PASS":"FAIL") << std::endl;
 std::cout << ((test.insert(mLong(14),5)==false)?"PASS":"FAIL") << std::endl;
 std::cout << ((test.retrieve(mLong(12))==1)?"PASS":"FAIL") << std::endl;
 std::cout << ((test.retrieve(mLong(14))==5)?"PASS":"FAIL") << std::endl;
 std::cout << ((test.retrieve(mLong(13))==-1)?"PASS":"FAIL") << std::endl;
}

Expected output

$ gcc dht.cc -lstdc++ -o dht && ./dht 
PASS
PASS
PASS
PASS
PASS
PASS
PASS