# include <cmath>
# include <cstdlib>
# include <cstring>
# include <ctime>
# include <fstream>
# include <iomanip>
# include <iostream>

using namespace std;

# define PI 3.141592654
# define NCITIES 413

int main ( int argc, char **argv );
double rand_nd ( double mean, double stddev );
void timestamp ( );

const char* city[NCITIES] = {
    "Abha",
    "Abidjan",
    "Abéché",
    "Accra",
    "Addis Ababa",
    "Adelaide",
    "Aden",
    "Ahvaz",
    "Albuquerque",
    "Alexandra",
    "Alexandria",
    "Algiers",
    "Alice Springs",
    "Almaty",
    "Amsterdam",
    "Anadyr",
    "Anchorage",
    "Andorra la Vella",
    "Ankara",
    "Antananarivo",
    "Antsiranana",
    "Arkhangelsk",
    "Ashgabat",
    "Asmara",
    "Assab",
    "Astana",
    "Athens",
    "Atlanta",
    "Auckland",
    "Austin",
    "Baghdad",
    "Baguio",
    "Baku",
    "Baltimore",
    "Bamako",
    "Bangkok",
    "Bangui",
    "Banjul",
    "Barcelona",
    "Bata",
    "Batumi",
    "Beijing",
    "Beirut",
    "Belgrade",
    "Belize City",
    "Benghazi",
    "Bergen",
    "Berlin",
    "Bilbao",
    "Birao",
    "Bishkek",
    "Bissau",
    "Blantyre",
    "Bloemfontein",
    "Boise",
    "Bordeaux",
    "Bosaso",
    "Boston",
    "Bouaké",
    "Bratislava",
    "Brazzaville",
    "Bridgetown",
    "Brisbane",
    "Brussels",
    "Bucharest",
    "Budapest",
    "Bujumbura",
    "Bulawayo",
    "Burnie",
    "Busan",
    "Cabo San Lucas",
    "Cairns",
    "Cairo",
    "Calgary",
    "Canberra",
    "Cape Town",
    "Changsha",
    "Charlotte",
    "Chiang Mai",
    "Chicago",
    "Chihuahua",
    "Chișinău",
    "Chittagong",
    "Chongqing",
    "Christchurch",
    "City of San Marino",
    "Colombo",
    "Columbus",
    "Conakry",
    "Copenhagen",
    "Cotonou",
    "Cracow",
    "Da Lat",
    "Da Nang",
    "Dakar",
    "Dallas",
    "Damascus",
    "Dampier",
    "Dar es Salaam",
    "Darwin",
    "Denpasar",
    "Denver",
    "Detroit",
    "Dhaka",
    "Dikson",
    "Dili",
    "Djibouti",
    "Dodoma",
    "Dolisie",
    "Douala",
    "Dubai",
    "Dublin",
    "Dunedin",
    "Durban",
    "Dushanbe",
    "Edinburgh",
    "Edmonton",
    "El Paso",
    "Entebbe",
    "Erbil",
    "Erzurum",
    "Fairbanks",
    "Fianarantsoa",
    "Flores Petén",
    "Frankfurt",
    "Fresno",
    "Fukuoka",
    "Gabès",
    "Gaborone",
    "Gagnoa",
    "Gangtok",
    "Garissa",
    "Garoua",
    "George Town",
    "Ghanzi",
    "Gjoa Haven",
    "Guadalajara",
    "Guangzhou",
    "Guatemala City",
    "Halifax",
    "Hamburg",
    "Hamilton",
    "Hanga Roa",
    "Hanoi",
    "Harare",
    "Harbin",
    "Hargeisa",
    "Hat Yai",
    "Havana",
    "Helsinki",
    "Heraklion",
    "Hiroshima",
    "Ho Chi Minh City",
    "Hobart",
    "Hong Kong",
    "Honiara",
    "Honolulu",
    "Houston",
    "Ifrane",
    "Indianapolis",
    "Iqaluit",
    "Irkutsk",
    "Istanbul",
    "İzmir",
    "Jacksonville",
    "Jakarta",
    "Jayapura",
    "Jerusalem",
    "Johannesburg",
    "Jos",
    "Juba",
    "Kabul",
    "Kampala",
    "Kandi",
    "Kankan",
    "Kano",
    "Kansas City",
    "Karachi",
    "Karonga",
    "Kathmandu",
    "Khartoum",
    "Kingston",
    "Kinshasa",
    "Kolkata",
    "Kuala Lumpur",
    "Kumasi",
    "Kunming",
    "Kuopio",
    "Kuwait City",
    "Kyiv",
    "Kyoto",
    "La Ceiba",
    "La Paz",
    "Lagos",
    "Lahore",
    "Lake Havasu City",
    "Lake Tekapo",
    "Las Palmas de Gran Canaria",
    "Las Vegas",
    "Launceston",
    "Lhasa",
    "Libreville",
    "Lisbon",
    "Livingstone",
    "Ljubljana",
    "Lodwar",
    "Lomé",
    "London",
    "Los Angeles",
    "Louisville",
    "Luanda",
    "Lubumbashi",
    "Lusaka",
    "Luxembourg City",
    "Lviv",
    "Lyon",
    "Madrid",
    "Mahajanga",
    "Makassar",
    "Makurdi",
    "Malabo",
    "Malé",
    "Managua",
    "Manama",
    "Mandalay",
    "Mango",
    "Manila",
    "Maputo",
    "Marrakesh",
    "Marseille",
    "Maun",
    "Medan",
    "Mek'ele",
    "Melbourne",
    "Memphis",
    "Mexicali",
    "Mexico City",
    "Miami",
    "Milan",
    "Milwaukee",
    "Minneapolis",
    "Minsk",
    "Mogadishu",
    "Mombasa",
    "Monaco",
    "Moncton",
    "Monterrey",
    "Montreal",
    "Moscow",
    "Mumbai",
    "Murmansk",
    "Muscat",
    "Mzuzu",
    "N'Djamena",
    "Naha",
    "Nairobi",
    "Nakhon Ratchasima",
    "Napier",
    "Napoli",
    "Nashville",
    "Nassau",
    "Ndola",
    "New Delhi",
    "New Orleans",
    "New York City",
    "Ngaoundéré",
    "Niamey",
    "Nicosia",
    "Niigata",
    "Nouadhibou",
    "Nouakchott",
    "Novosibirsk",
    "Nuuk",
    "Odesa",
    "Odienné",
    "Oklahoma City",
    "Omaha",
    "Oranjestad",
    "Oslo",
    "Ottawa",
    "Ouagadougou",
    "Ouahigouya",
    "Ouarzazate",
    "Oulu",
    "Palembang",
    "Palermo",
    "Palm Springs",
    "Palmerston North",
    "Panama City",
    "Parakou",
    "Paris",
    "Perth",
    "Petropavlovsk-Kamchatsky",
    "Philadelphia",
    "Phnom Penh",
    "Phoenix",
    "Pittsburgh",
    "Podgorica",
    "Pointe-Noire",
    "Pontianak",
    "Port Moresby",
    "Port Sudan",
    "Port Vila",
    "Port-Gentil",
    "Portland {OR}",
    "Porto",
    "Prague",
    "Praia",
    "Pretoria",
    "Pyongyang",
    "Rabat",
    "Rangpur",
    "Reggane",
    "Reykjavík",
    "Riga",
    "Riyadh",
    "Rome",
    "Roseau",
    "Rostov-on-Don",
    "Sacramento",
    "Saint Petersburg",
    "Saint-Pierre",
    "Salt Lake City",
    "San Antonio",
    "San Diego",
    "San Francisco",
    "San Jose",
    "San José",
    "San Juan",
    "San Salvador",
    "Sana'a",
    "Santo Domingo",
    "Sapporo",
    "Sarajevo",
    "Saskatoon",
    "Seattle",
    "Ségou",
    "Seoul",
    "Seville",
    "Shanghai",
    "Singapore",
    "Skopje",
    "Sochi",
    "Sofia",
    "Sokoto",
    "Split",
    "St. John's",
    "St. Louis",
    "Stockholm",
    "Surabaya",
    "Suva",
    "Suwałki",
    "Sydney",
    "Tabora",
    "Tabriz",
    "Taipei",
    "Tallinn",
    "Tamale",
    "Tamanrasset",
    "Tampa",
    "Tashkent",
    "Tauranga",
    "Tbilisi",
    "Tegucigalpa",
    "Tehran",
    "Tel Aviv",
    "Thessaloniki",
    "Thiès",
    "Tijuana",
    "Timbuktu",
    "Tirana",
    "Toamasina",
    "Tokyo",
    "Toliara",
    "Toluca",
    "Toronto",
    "Tripoli",
    "Tromsø",
    "Tucson",
    "Tunis",
    "Ulaanbaatar",
    "Upington",
    "Ürümqi",
    "Vaduz",
    "Valencia",
    "Valletta",
    "Vancouver",
    "Veracruz",
    "Vienna",
    "Vientiane",
    "Villahermosa",
    "Vilnius",
    "Virginia Beach",
    "Vladivostok",
    "Warsaw",
    "Washington DC",
    "Wau",
    "Wellington",
    "Whitehorse",
    "Wichita",
    "Willemstad",
    "Winnipeg",
    "Wrocław",
    "Xi'an",
    "Yakutsk",
    "Yangon",
    "Yaoundé",
    "Yellowknife",
    "Yerevan",
    "Yinchuan",
    "Zagreb",
    "Zanzibar City",
    "Zürich"
};

const double mean[NCITIES] = {
    18.0,
    26.0,
    29.4,
    26.4,
    16.0,
    17.3,
    29.1,
    25.4,
    14.0,
    11.0,
    20.0,
    18.2,
    21.0,
    10.0,
    10.2,
    -6.9,
    2.8,
    9.8,
    12.0,
    17.9,
    25.2,
    1.3,
    17.1,
    15.6,
    30.5,
    3.5,
    19.2,
    17.0,
    15.2,
    20.7,
    22.77,
    19.5,
    15.1,
    13.1,
    27.8,
    28.6,
    26.0,
    26.0,
    18.2,
    25.1,
    14.0,
    12.9,
    20.9,
    12.5,
    26.7,
    19.9,
    7.7,
    10.3,
    14.7,
    26.5,
    11.3,
    27.0,
    22.2,
    15.6,
    11.4,
    14.2,
    30.0,
    10.9,
    26.0,
    10.5,
    25.0,
    27.0,
    21.4,
    10.5,
    10.8,
    11.3,
    23.8,
    18.9,
    13.1,
    15.0,
    23.9,
    25.0,
    21.4,
    4.4,
    13.1,
    16.2,
    17.4,
    16.1,
    25.8,
    9.8,
    18.6,
    10.2,
    25.9,
    18.6,
    12.2,
    11.8,
    27.4,
    11.7,
    26.4,
    9.1,
    27.2,
    9.3,
    17.9,
    25.8,
    24.0,
    19.0,
    17.0,
    26.4,
    25.8,
    27.6,
    23.7,
    10.4,
    10.0,
    25.9,
    -11.1,
    26.6,
    29.9,
    22.7,
    24.0,
    26.7,
    26.9,
    9.8,
    11.1,
    20.6,
    14.7,
    9.3,
    4.2,
    18.1,
    21.0,
    19.5,
    5.1,
    -2.3,
    17.9,
    26.4,
    10.6,
    17.9,
    17.0,
    19.5,
    21.0,
    26.0,
    15.2,
    29.3,
    28.3,
    27.9,
    21.4,
    -14.4,
    20.9,
    22.4,
    20.4,
    7.5,
    9.7,
    13.8,
    20.5,
    23.6,
    18.4,
    5.0,
    21.7,
    27.0,
    25.2,
    5.9,
    18.9,
    16.3,
    27.4,
    12.7,
    23.3,
    26.5,
    25.4,
    20.8,
    11.4,
    11.8,
    -9.3,
    1.0,
    13.9,
    17.9,
    20.3,
    26.7,
    27.0,
    18.3,
    15.5,
    22.8,
    27.8,
    12.1,
    20.0,
    27.7,
    26.5,
    26.4,
    12.5,
    26.0,
    24.4,
    18.3,
    29.9,
    27.4,
    25.3,
    26.7,
    27.3,
    26.0,
    15.7,
    3.4,
    25.7,
    8.4,
    15.8,
    26.2,
    23.7,
    26.8,
    24.3,
    23.7,
    8.7,
    21.2,
    20.3,
    13.1,
    7.6,
    25.9,
    17.5,
    21.8,
    10.9,
    29.3,
    26.9,
    11.3,
    18.6,
    13.9,
    25.8,
    20.8,
    19.9,
    9.3,
    7.8,
    12.5,
    15.0,
    26.3,
    26.7,
    26.0,
    26.3,
    28.0,
    27.3,
    26.5,
    28.0,
    28.1,
    28.4,
    22.8,
    19.6,
    15.8,
    22.4,
    26.5,
    22.7,
    15.1,
    17.2,
    23.1,
    17.5,
    24.9,
    13.0,
    8.9,
    7.8,
    6.7,
    27.1,
    26.3,
    16.4,
    6.1,
    22.3,
    6.8,
    5.8,
    27.1,
    0.6,
    28.0,
    17.7,
    28.3,
    23.1,
    17.8,
    27.3,
    14.6,
    15.9,
    15.4,
    24.6,
    20.3,
    25.0,
    20.7,
    12.9,
    22.0,
    29.3,
    19.7,
    13.9,
    21.3,
    25.7,
    1.7,
    -1.4,
    10.7,
    26.0,
    15.9,
    10.6,
    28.1,
    5.7,
    6.6,
    28.3,
    28.6,
    18.9,
    2.7,
    27.3,
    18.5,
    24.5,
    13.2,
    28.0,
    26.8,
    12.3,
    18.7,
    1.9,
    13.2,
    28.3,
    23.9,
    10.8,
    15.3,
    26.1,
    27.7,
    26.9,
    28.4,
    24.3,
    26.0,
    12.4,
    15.7,
    8.4,
    24.4,
    18.2,
    10.8,
    17.2,
    24.4,
    28.3,
    4.3,
    6.2,
    26.0,
    15.2,
    26.2,
    9.9,
    16.3,
    5.8,
    5.7,
    11.6,
    20.8,
    17.8,
    14.6,
    16.4,
    22.6,
    27.2,
    23.1,
    20.0,
    25.9,
    8.9,
    10.1,
    3.3,
    11.3,
    28.0,
    12.5,
    19.2,
    16.7,
    27.0,
    12.4,
    14.2,
    10.6,
    28.0,
    16.1,
    5.0,
    13.9,
    6.6,
    27.1,
    25.6,
    7.2,
    17.7,
    23.0,
    12.6,
    23.0,
    6.4,
    27.9,
    21.7,
    22.9,
    14.8,
    14.8,
    12.9,
    21.7,
    17.0,
    20.0,
    16.0,
    24.0,
    17.8,
    28.0,
    15.2,
    23.4,
    15.4,
    24.1,
    12.4,
    9.4,
    20.0,
    2.9,
    20.9,
    18.4,
    -0.4,
    20.4,
    7.4,
    10.1,
    18.3,
    18.8,
    10.4,
    25.4,
    10.4,
    25.9,
    27.1,
    6.0,
    15.8,
    4.9,
    8.5,
    14.6,
    27.8,
    12.9,
    -0.1,
    13.9,
    28.0,
    3.0,
    9.6,
    14.1,
    -8.8,
    27.5,
    23.8,
    -4.3,
    12.4,
    9.0,
    10.7,
    26.0,
    9.3};
//****************************************************************************80

int main ( int argc, char **argv )

//****************************************************************************80
//
//  Purpose:
//
//    brc_data() generates a data file for the one billion row challenge.
//
//  Licensing:
//
//    This code is distributed under the MIT license. 
//
//  Modified:
//
//    19 October 2024
//
{
  int c;
  string filename;
  int i;
  long n;
  int ncities;
  ofstream output;
  double run_time;
  double t;
  clock_t tstart;
  clock_t tstop;

  timestamp ( );

  cout << "\n";
  cout << "brc_data():\n";
  cout << "  C++ version\n";
  cout << "  Generate data for the one billion row challenge.\n";
//
//  If no arguments, print a message and terminate.
//
  if ( argc <= 1 )
  {
    cout << "\n";
    cout <<  "usage: brc_data n\n";
    cout <<  "  where 'n' is the number of observations to generate.\n";
    exit ( EXIT_SUCCESS );
  }

  if ( argc <= 2 )
  {
    filename = "measurements.txt";
  }
  else
  {
    filename = argv[2];
  }

  output.open ( filename.c_str ( ) );

  if ( ! output )
  {
    cout << "  Error creating file '" << filename << "'\n";
    exit ( EXIT_FAILURE );
  }

  tstart = clock ( );
//
//  n is the number of observations to be generated.
//
  n = strtol ( argv[1], NULL, 10 );
//
//  Figure out number of cities.
//
  ncities = NCITIES;
  cout << "  Number of weather stations is " << ncities << ".\n";
//
//  For each observation, choose a city "c" uniformly at random, 
//  generate a temperature measurement "t" with normal distribution
//  with variance of 10, and write it to the file.
//
  for ( i = 0; i < n; i++ )
  {
    c = rand() % ncities;
    t = rand_nd ( mean[c], 10 );
    output << city[c] << ';' << t;
  }

  output.close ( );
  tstop = clock ( );
  run_time = ( double ) ( tstop - tstart ) * 1000 / ( double ) CLOCKS_PER_SEC;

  cout << "  Temperature records stored in file '" << filename << "'.\n";
  cout << "  Number of records is " << n << ".\n";
  cout << "  Run time was " << run_time << " milliseconds.\n", 
//
//  Terminate.
//
  cout << "\n";
  cout << "brc_data():\n";
  cout << "  Normal end of execution.\n";

  timestamp ( );

  return 0;
}
//****************************************************************************80

double rand_nd ( double mean, double stddev )

//****************************************************************************80
//
//  Purpose:
//
//    rand_nd() returns a normally distributed random value.
//
//  Discussion:
//
//    The Box-Muller method is used to generate the values.
//
//  Licensing:
//
//    This code is distributed under the MIT license. 
//
//  Modified:
//
//    10 May 2024
//
//  Input:
//
//    double mean, stddev: the desired mean and standard deviation.
//
//  Output:
//
//    double rand_nd: a random value from the normal distribution
//    with given mean and standard deviation.
//
{
  static int phase = 0;
  static double U;
  static double V;
  double Z;

  if ( phase == 0 )
  {
    U = ( rand() + 1.0 ) / ( RAND_MAX + 2.0 );
    V = rand() / ( RAND_MAX + 1.0 );
    Z = sqrt ( -2.0 * log ( U ) ) * sin ( 2.0 * PI * V );
  } 
  else
  {
    Z = sqrt ( -2.0 * log ( U ) ) * cos ( 2.0 * PI * V );
  }
  phase = 1 - phase;

  return Z * stddev + mean;
}
//****************************************************************************80

void timestamp ( )

//****************************************************************************80
//
//  Purpose:
//
//    timestamp() prints the current YMDHMS date as a time stamp.
//
//  Example:
//
//    31 May 2001 09:45:54 AM
//
//  Licensing:
//
//    This code is distributed under the MIT license. 
//
//  Modified:
//
//    19 March 2018
//
//  Author:
//
//    John Burkardt
//
{
# define TIME_SIZE 40

  static char time_buffer[TIME_SIZE];
  const struct std::tm *tm_ptr;
  std::time_t now;

  now = std::time ( NULL );
  tm_ptr = std::localtime ( &now );

  std::strftime ( time_buffer, TIME_SIZE, "%d %B %Y %I:%M:%S %p", tm_ptr );

  std::cout << time_buffer << "\n";

  return;
# undef TIME_SIZE
}