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

# include "tsp_att48.h"

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

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

int main ( )

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

    tsp_att48_test() tests tsp_att48().

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    26 July 2026

  Author:

    John Burkardt
*/
{
  double cost;
  int *att48_order;
  double *att48_xy;
  int i;
  int i2;
  int n;
  double *x2;

  timestamp ( );

  printf ( "\n" );
  printf ( "tsp_att48_test():\n" );
  printf ( "  C version\n" );
  printf ( "  Test tsp_att48(), which returns the AT&T 48 city\n" );
  printf ( "  traveling salesperson problem challenge data.\n" );

  n = 48;
  att48_order = tsp_att48_order ( );
  att48_xy = tsp_att48_xy ( );

  printf ( "\n" );
  printf ( "  City coordinates:\n" );
  printf ( "\n" );
  for ( i = 0; i < n; i++ )
  {
    printf ( "  %2d  %8g  %8g\n", i, att48_xy[2*i], att48_xy[2*i+1] );
  }
/*
  Report the minimal cost.
*/
  cost = tsp_tour_cost ( n, att48_xy, att48_order );
  printf ( "\n" );
  printf ( "  Cost of shortest round trip is %g\n", cost );
/*
  Copy the city locations in TSP order.
*/
  x2 = ( double * ) malloc ( ( n + 1 ) * 2 * sizeof ( double ) );
 
  for ( i2 = 0; i2 <= n; i2++ )
  {
    if ( i2 < n )
    {
      i = att48_order[i2];
    }
    else
    {
      i = att48_order[0];
    }
    x2[2*i2]   = att48_xy[2*i];
    x2[2*i2+1] = att48_xy[2*i+1];
  }
/*
  Display the locations.
*/
  tsp_display ( "att48", n + 1, x2 );
/*
  Free memory.
*/
  free ( att48_order );
  free ( att48_xy );
  free ( x2 );
/*
  Terminate.
*/
  printf ( "\n" );
  printf ( "tsp_att48_test():\n" );
  printf ( "  Normal end of execution.\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;
}
/******************************************************************************/

double tsp_tour_cost ( int n, double *x, int *order )

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

    tsp_tour_cost() evaluates the cost of a round trip.

  Licensing:

    This code is distributed under the MIT license.

  Modified:

    18 June 2026

  Author:

    John Burkardt

  Input:

    int n: the number of cities.

    double x[n,2]: the city locations.

    int order[n]: the order in which the cities are visited.

  Output:

    double cost: the cost of the route.
*/
{
  double cost;
  int from;
  int to;

  cost = 0.0;
  from = n - 1;
  for ( to = 0; to < n; to++ )
  {
    cost = cost + sqrt ( pow ( x[order[from]*2]   - x[order[to]*2],   2 )
                       + pow ( x[order[from]*2+1] - x[order[to]*2+1], 2 ) );
    from = to;
  }

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

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
}