unorderd_map.cpp

#include <iostream>
#include <vector>
#include <unordered_map>
#include <string>
using std::vector;
using std::cout;
using std::unordered_map;
using std::string;


// check if the key is present in the hash-table or not
bool isset_key(unordered_map<string, vector<string>> dict, string key)
{
  if (dict.find(key) == dict.end())
    return false;
  return true;
}


int main() {

  // unordered_map <string, vector<string>> dict;
  unordered_map<string, vector<string>> dict = {
    {"本",{"ほん (hon)", "もと (moto)" }}
  };
  // Add another entry to the map
  dict["日"] = vector<string> {"にち (nichi)", "ひ (hi)"};

  string key = "本";
  cout << "key: " << key << "\n";
  auto definitions = dict[key];
  for (const string& definition : definitions) {
    cout << definition << "\n";
  }

  key = "四";
  if (!isset_key(dict, key)) {
    cout << "The key '四 (four)' is not in the dictionary." << "\n";
  }

  /* > g++ -std=c++11 unorderd_map.cpp&& ./a.out
  key: 本
  ほん (hon)
  もと (moto)
  The key '四 (four)' is not in the dictionary.
  */

}