# include <math.h>
# include <stdio.h>
# include <stdlib.h>
# include <string.h>
# include <time.h>

# include "tsp_nearest.h"

int main ( );
void timestamp ( );
void tsp_display ( char *prefix, int n, double *x2 );

/******************************************************************************/

int main ( )

/******************************************************************************/
/*
  Purpose:

    tsp_nearest_test() tests tsp_nearest().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    08 July 2026

  Author:

    John Burkardt
*/
{
  double cost;
  double d;
  int i;
  int i1;
  int i2;
  int j1;
  int j2;
  int n = 48;
  int order[48];
  char prefix[] = "att48";
  static double x[48*2] = {
     6734, 1453, 
    2233,   10, 
    5530, 1424, 
     401,  841, 
    3082, 1644, 
    7608, 4458, 
    7573, 3716, 
    7265, 1268, 
    6898, 1885, 
    1112, 2049, 
    5468, 2606, 
    5989, 2873, 
    4706, 2674, 
    4612, 2035, 
    6347, 2683, 
    6107,  669, 
    7611, 5184, 
    7462, 3590, 
    7732, 4723, 
    5900, 3561, 
    4483, 3369, 
    6101, 1110, 
    5199, 2182, 
    1633, 2809, 
    4307, 2322, 
     675, 1006, 
    7555, 4819, 
    7541, 3981, 
    3177,  756, 
    7352, 4506, 
    7545, 2801, 
    3245, 3305, 
    6426, 3173, 
    4608, 1198, 
      23, 2216, 
    7248, 3779, 
    7762, 4595, 
    7392, 2244, 
    3484, 2829, 
    6271, 2135, 
    4985,  140, 
    1916, 1569, 
    7280, 4899, 
    7509, 3239, 
      10, 2676, 
    6807, 2993, 
    5185, 3258, 
    3023, 1942 };
  double *x2;

  timestamp ( );

  printf ( "\n" );
  printf ( "tsp_nearest_test():\n" );
  printf ( "  C version\n" );
  printf ( "  Test tsp_nearest(), which uses the nearest neighbor method\n" );
  printf ( "  to construct a round trip for the traveling salesman problem.\n" );

  tsp_nearest ( n, x, order, &cost );
/*
  Report.
*/
  printf ( "\n" );
  printf ( "  The best itinerary found:\n" );
  printf ( "\n" );
  printf ( "  Step  From  To        Distance\n" );
  printf ( "\n" );

  for ( i1 = 0; i1 < n; i1++ )
  {
    i2 = ( ( i1 + 1 ) % n );
    j1 = order[i1];
    j2 = order[i2];
    d = sqrt ( pow ( x[j1*2]   - x[j2*2],   2 )
             + pow ( x[j1*2+1] - x[j2*2+1], 2 ) );
    printf ( "  %4d    %2d  %2d  %14.6g\n", i1, j1, j2, d );
    cost = cost + d;
  }
  printf ( "  ----    --  --  --------------\n" );
  printf ( "  cost:           %14.6g\n", cost );
/*
  Create the circuit data with transposition, reordering and wrap-around.
*/
  x2 = ( double * ) malloc ( ( n + 1 ) * 2 * sizeof ( double ) );

  for ( i2 = 0; i2 <= n; i2++ )
  {
    if ( i2 < n )
    {
      i = order[i2];
    }
    else
    {
      i = order[0];
    }
    x2[i2*2]   = x[i*2];
    x2[i2*2+1] = x[i*2+1];
  }
/*
  Send the data to the plotter.
*/
  tsp_display ( prefix, n + 1, x2 );

  free ( x2 );
/*
  Terminate.
*/
  printf ( "\n" );
  printf ( "tsp_nearest_test():\n" );
  printf ( "  Normal end of execution.\n" );
  printf ( "\n" );
  timestamp ( );

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

void tsp_display ( char *prefix, int n, double *x2 )

/******************************************************************************/
/*
  Purpose:

    tsp_display() plots cities and a tour connecting them.

  Discussion:

    If a "round trip" is desired, then the x2 array must repeat the
    first city at the end.

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    12 June 2026

  Author:

    John Burkardt

  Input:

    char *prefix: a string that defines the name of
    the problem.  It is also used to create file names needed for
    input to gnuplot.

    int n: the number of cities.

    double x[n*2]: the x and y coordinates of the cities.
*/
{
  char command_filename[80];
  FILE *command;
  FILE *data;
  char data_filename[80];
  int i;
/*
  Create the data file.
*/
  strcpy ( data_filename, prefix );
  strcat ( data_filename, "_data.txt" );
  data = fopen ( data_filename, "wt" );
  for ( i = 0; i < n; i++ )
  {
    fprintf ( data, "%14.6g  %14.6g\n", x2[2*i], x2[2*i+1] );
  }
  fclose ( data );
  printf ( "  Created data file '%s'\n", data_filename );
/*
  Create the command file.
*/
  strcpy ( command_filename, prefix );
  strcat ( command_filename, "_commands.txt" );
  command = fopen ( command_filename, "wt" );

  fprintf ( command, "# %s\n", command_filename );
  fprintf ( command, "#\n" );
  fprintf ( command, "# Usage:\n" );
  fprintf ( command, "#  gnuplot < %s\n", command_filename );
  fprintf ( command, "#\n" );
  fprintf ( command, "set term png\n" );
  fprintf ( command, "set output '%s.png'\n", prefix );
  fprintf ( command, "set xlabel '<--- X --->'\n" );
  fprintf ( command, "set ylabel '<--- Y --->'\n" );
  fprintf ( command, "set title '%s'\n", prefix );
  fprintf ( command, "set grid\n" );
  fprintf ( command, "unset key\n" );
  fprintf ( command, "set style data lines\n" );
  fprintf ( command, "plot '%s' using 1:2 lw 3 linecolor rgb 'blue', \\\n", data_filename );
  fprintf ( command, "     '%s' using 1:2 with points pointtype 7 pointsize 3 linecolor rgb 'green'\n", data_filename );
  fprintf ( command, "quit\n" );
  fclose ( command );
  printf ( "  Created command file '%s'\n", command_filename );

  return;
}
/******************************************************************************/

void timestamp ( )

/******************************************************************************/
/*
  Purpose:
 
    timestamp() prints the current YMDHMS date as a time stamp.

  Example:

    17 June 2014 09:45:54 AM

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    01 May 2021

  Author:

    John Burkardt
*/
{
# define TIME_SIZE 40

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

  now = time ( NULL );
  tm = localtime ( &now );

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

  printf ( "%s\n", time_buffer );

  return;
# undef TIME_SIZE
}