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ls.c
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ls.c
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/*
AAAA CCCC OOOO TTTTTT SSSSS PPPPP
AA AA CC OO OO TT SS PP PP
AAAAAA CC OO OO TT SSSS PPPPP
AA AA CC OO OO TT SS PP
AA AA CCCC OOOO TT SSSSS PP
######################################################
########## ACO algorithms for the TSP ##########
######################################################
Version: 1.0
File: ls.c
Author: Thomas Stuetzle
Purpose: implementation of local search routines
Check: README and gpl.txt
Copyright (C) 1999 Thomas Stuetzle
*/
/***************************************************************************
Program's name: acotsp
Ant Colony Optimization algorithms (AS, ACS, EAS, RAS, MMAS, BWAS) for the
symmetric TSP
Copyright (C) 2004 Thomas Stuetzle
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
email: stuetzle no@spam ulb.ac.be
mail address: Universite libre de Bruxelles
IRIDIA, CP 194/6
Av. F. Roosevelt 50
B-1050 Brussels
Belgium
***************************************************************************/
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include <limits.h>
#include "ls.h"
#include "InOut.h"
#include "TSP.h"
#include "ants.h"
#include "utilities.h"
long int ls_flag; /* indicates whether and which local search is used */
long int nn_ls; /* maximal depth of nearest neighbour lists used in the
local search */
long int dlb_flag = TRUE; /* flag indicating whether don't look bits are used. I recommend
to always use it if local search is applied */
long int * generate_random_permutation( long int n )
/*
FUNCTION: generate a random permutation of the integers 0 .. n-1
INPUT: length of the array
OUTPUT: pointer to the random permutation
(SIDE)EFFECTS: the array holding the random permutation is allocated in this
function. Don't forget to free again the memory!
COMMENTS: only needed by the local search procedures
*/
{
long int i, help, node, tot_assigned = 0;
double rnd;
long int *r;
r = malloc(n * sizeof(long int));
for ( i = 0 ; i < n; i++)
r[i] = i;
for ( i = 0 ; i < n ; i++ ) {
/* find (randomly) an index for a free unit */
rnd = ran01 ( &seed );
node = (long int) (rnd * (n - tot_assigned));
assert( i + node < n );
help = r[i];
r[i] = r[i+node];
r[i+node] = help;
tot_assigned++;
}
return r;
}
void two_opt_first( long int *tour )
/*
FUNCTION: 2-opt a tour
INPUT: pointer to the tour that undergoes local optimization
OUTPUT: none
(SIDE)EFFECTS: tour is 2-opt
COMMENTS: the neighbourhood is scanned in random order (this need
not be the best possible choice). Concerning the speed-ups used
here consult, for example, Chapter 8 of
Holger H. Hoos and Thomas Stuetzle,
Stochastic Local Search---Foundations and Applications,
Morgan Kaufmann Publishers, 2004.
or some of the papers online available from David S. Johnson.
*/
{
long int c1, c2; /* cities considered for an exchange */
long int s_c1, s_c2; /* successor cities of c1 and c2 */
long int p_c1, p_c2; /* predecessor cities of c1 and c2 */
long int pos_c1, pos_c2; /* positions of cities c1, c2 */
long int i, j, h, l;
long int improvement_flag, help, n_improves = 0, n_exchanges=0;
long int h1=0, h2=0, h3=0, h4=0;
long int radius; /* radius of nn-search */
long int gain = 0;
long int *random_vector;
long int *pos; /* positions of cities in tour */
long int *dlb; /* vector containing don't look bits */
pos = malloc(n * sizeof(long int));
dlb = malloc(n * sizeof(long int));
for ( i = 0 ; i < n ; i++ ) {
pos[tour[i]] = i;
dlb[i] = FALSE;
}
improvement_flag = TRUE;
random_vector = generate_random_permutation( n );
while ( improvement_flag ) {
improvement_flag = FALSE;
for (l = 0 ; l < n; l++) {
c1 = random_vector[l];
DEBUG ( assert ( c1 < n && c1 >= 0); )
if ( dlb_flag && dlb[c1] )
continue;
pos_c1 = pos[c1];
s_c1 = tour[pos_c1+1];
radius = instance.distance[c1][s_c1];
/* First search for c1's nearest neighbours, use successor of c1 */
for ( h = 0 ; h < nn_ls ; h++ ) {
c2 = instance.nn_list[c1][h]; /* exchange partner, determine its position */
if ( radius > instance.distance[c1][c2] ) {
s_c2 = tour[pos[c2]+1];
gain = - radius + instance.distance[c1][c2] +
instance.distance[s_c1][s_c2] - instance.distance[c2][s_c2];
if ( gain < 0 ) {
h1 = c1; h2 = s_c1; h3 = c2; h4 = s_c2;
goto exchange2opt;
}
}
else
break;
}
/* Search one for next c1's h-nearest neighbours, use predecessor c1 */
if (pos_c1 > 0)
p_c1 = tour[pos_c1-1];
else
p_c1 = tour[n-1];
radius = instance.distance[p_c1][c1];
for ( h = 0 ; h < nn_ls ; h++ ) {
c2 = instance.nn_list[c1][h]; /* exchange partner, determine its position */
if ( radius > instance.distance[c1][c2] ) {
pos_c2 = pos[c2];
if (pos_c2 > 0)
p_c2 = tour[pos_c2-1];
else
p_c2 = tour[n-1];
if ( p_c2 == c1 )
continue;
if ( p_c1 == c2 )
continue;
gain = - radius + instance.distance[c1][c2] +
instance.distance[p_c1][p_c2] - instance.distance[p_c2][c2];
if ( gain < 0 ) {
h1 = p_c1; h2 = c1; h3 = p_c2; h4 = c2;
goto exchange2opt;
}
}
else
break;
}
/* No exchange */
dlb[c1] = TRUE;
continue;
exchange2opt:
n_exchanges++;
improvement_flag = TRUE;
dlb[h1] = FALSE; dlb[h2] = FALSE;
dlb[h3] = FALSE; dlb[h4] = FALSE;
/* Now perform move */
if ( pos[h3] < pos[h1] ) {
help = h1; h1 = h3; h3 = help;
help = h2; h2 = h4; h4 = help;
}
if ( pos[h3] - pos[h2] < n / 2 + 1) {
/* reverse inner part from pos[h2] to pos[h3] */
i = pos[h2]; j = pos[h3];
while (i < j) {
c1 = tour[i];
c2 = tour[j];
tour[i] = c2;
tour[j] = c1;
pos[c1] = j;
pos[c2] = i;
i++; j--;
}
}
else {
/* reverse outer part from pos[h4] to pos[h1] */
i = pos[h1]; j = pos[h4];
if ( j > i )
help = n - (j - i) + 1;
else
help = (i - j) + 1;
help = help / 2;
for ( h = 0 ; h < help ; h++ ) {
c1 = tour[i];
c2 = tour[j];
tour[i] = c2;
tour[j] = c1;
pos[c1] = j;
pos[c2] = i;
i--; j++;
if ( i < 0 )
i = n-1;
if ( j >= n )
j = 0;
}
tour[n] = tour[0];
}
}
if ( improvement_flag ) {
n_improves++;
}
}
free( random_vector );
free( dlb );
free( pos );
}
void two_h_opt_first( long int *tour )
/*
FUNCTION: 2-h-opt a tour
INPUT: pointer to the tour that undergoes local optimization
OUTPUT: none
(SIDE)EFFECTS: tour is 2-h-opt
COMMENTS: for details on 2-h-opt see J. L. Bentley. Fast algorithms for geometric
traveling salesman problems. ORSA Journal on Computing,
4(4):387--411, 1992.
The neighbourhood is scanned in random order (this need
not be the best possible choice). Concerning the speed-ups used
here consult, for example, Chapter 8 of
Holger H. Hoos and Thomas Stuetzle,
Stochastic Local Search---Foundations and Applications,
Morgan Kaufmann Publishers, 2004.
or some of the papers online available from David S. Johnson.
*/
{
long int c1, c2; /* cities considered for an exchange */
long int s_c1, s_c2; /* successors of c1 and c2 */
long int p_c1, p_c2; /* predecessors of c1 and c2 */
long int pos_c1, pos_c2; /* positions of cities c1, c2 */
long int i, j, h, l;
long int improvement_flag, improve_node;
long int h1=0, h2=0, h3=0, h4=0, h5=0, help;
long int radius; /* radius of nn-search */
long int gain = 0;
long int *random_vector;
long int two_move, node_move;
long int *pos; /* positions of cities in tour */
long int *dlb; /* vector containing don't look bits */
pos = malloc(n * sizeof(long int));
dlb = malloc(n * sizeof(long int));
for ( i = 0 ; i < n ; i++ ) {
pos[tour[i]] = i;
dlb[i] = FALSE;
}
improvement_flag = TRUE;
random_vector = generate_random_permutation( n );
while ( improvement_flag ) {
improvement_flag = FALSE; two_move = FALSE; node_move = FALSE;
for (l = 0 ; l < n; l++) {
c1 = random_vector[l];
DEBUG ( assert ( c1 < n && c1 >= 0); )
if ( dlb_flag && dlb[c1] )
continue;
improve_node = FALSE;
pos_c1 = pos[c1];
s_c1 = tour[pos_c1+1];
radius = instance.distance[c1][s_c1];
/* First search for c1's nearest neighbours, use successor of c1 */
for ( h = 0 ; h < nn_ls ; h++ ) {
c2 = instance.nn_list[c1][h]; /* exchange partner, determine its position */
if ( radius > instance.distance[c1][c2] ) {
pos_c2 = pos[c2];
s_c2 = tour[pos_c2+1];
gain = - radius + instance.distance[c1][c2] +
instance.distance[s_c1][s_c2] - instance.distance[c2][s_c2];
if ( gain < 0 ) {
h1 = c1; h2 = s_c1; h3 = c2; h4 = s_c2;
improve_node = TRUE; two_move = TRUE; node_move = FALSE;
goto exchange;
}
if (pos_c2 > 0)
p_c2 = tour[pos_c2-1];
else
p_c2 = tour[n-1];
gain = - radius + instance.distance[c1][c2] + instance.distance[c2][s_c1]
+ instance.distance[p_c2][s_c2] - instance.distance[c2][s_c2]
- instance.distance[p_c2][c2];
if ( c2 == s_c1 )
gain = 0;
if ( p_c2 == s_c1 )
gain = 0;
gain = 0;
if ( gain < 0 ) {
h1 = c1; h2 = s_c1; h3 = c2; h4 = p_c2; h5 = s_c2;
improve_node = TRUE; node_move = TRUE; two_move = FALSE;
goto exchange;
}
}
else
break;
}
/* Second search for c1's nearest neighbours, use predecessor c1 */
if (pos_c1 > 0)
p_c1 = tour[pos_c1-1];
else
p_c1 = tour[n-1];
radius = instance.distance[p_c1][c1];
for ( h = 0 ; h < nn_ls ; h++ ) {
c2 = instance.nn_list[c1][h]; /* exchange partner, determine its position */
if ( radius > instance.distance[c1][c2] ) {
pos_c2 = pos[c2];
if (pos_c2 > 0)
p_c2 = tour[pos_c2-1];
else
p_c2 = tour[n-1];
if ( p_c2 == c1 )
continue;
if ( p_c1 == c2 )
continue;
gain = - radius + instance.distance[c1][c2] +
instance.distance[p_c1][p_c2] - instance.distance[p_c2][c2];
if ( gain < 0 ) {
h1 = p_c1; h2 = c1; h3 = p_c2; h4 = c2;
improve_node = TRUE; two_move = TRUE; node_move = FALSE;
goto exchange;
}
s_c2 = tour[pos[c2]+1];
gain = - radius + instance.distance[c2][c1] + instance.distance[p_c1][c2]
+ instance.distance[p_c2][s_c2] - instance.distance[c2][s_c2]
- instance.distance[p_c2][c2];
if ( p_c1 == c2 )
gain = 0;
if ( p_c1 == s_c2 )
gain = 0;
if ( gain < 0 ) {
h1 = p_c1; h2 = c1; h3 = c2; h4 = p_c2; h5 = s_c2;
improve_node = TRUE; node_move = TRUE; two_move = FALSE;
goto exchange;
}
}
else
break;
}
exchange:
if (improve_node) {
if ( two_move ) {
improvement_flag = TRUE;
dlb[h1] = FALSE; dlb[h2] = FALSE;
dlb[h3] = FALSE; dlb[h4] = FALSE;
/* Now perform move */
if ( pos[h3] < pos[h1] ) {
help = h1; h1 = h3; h3 = help;
help = h2; h2 = h4; h4 = help;
}
if ( pos[h3] - pos[h2] < n / 2 + 1) {
/* reverse inner part from pos[h2] to pos[h3] */
i = pos[h2]; j = pos[h3];
while (i < j) {
c1 = tour[i];
c2 = tour[j];
tour[i] = c2;
tour[j] = c1;
pos[c1] = j;
pos[c2] = i;
i++; j--;
}
}
else {
/* reverse outer part from pos[h4] to pos[h1] */
i = pos[h1]; j = pos[h4];
if ( j > i )
help = n - (j - i) + 1;
else
help = (i - j) + 1;
help = help / 2;
for ( h = 0 ; h < help ; h++ ) {
c1 = tour[i];
c2 = tour[j];
tour[i] = c2;
tour[j] = c1;
pos[c1] = j;
pos[c2] = i;
i--; j++;
if ( i < 0 )
i = n-1;
if ( j >= n )
j = 0;
}
tour[n] = tour[0];
}
} else if ( node_move ) {
improvement_flag = TRUE;
dlb[h1] = FALSE; dlb[h2] = FALSE; dlb[h3] = FALSE;
dlb[h4] = FALSE; dlb[h5] = FALSE;
/* Now perform move */
if ( pos[h3] < pos[h1] ) {
help = pos[h1] - pos[h3];
i = pos[h3];
for ( h = 0 ; h < help ; h++ ) {
c1 = tour[i+1];
tour[i] = c1;
pos[c1] = i;
i++;
}
tour[i] = h3;
pos[h3] = i;
tour[n] = tour[0];
} else {
/* pos[h3] > pos[h1] */
help = pos[h3] - pos[h1];
/* if ( help < n / 2 + 1) { */
i = pos[h3];
for ( h = 0 ; h < help - 1 ; h++ ) {
c1 = tour[i-1];
tour[i] = c1;
pos[c1] = i;
i--;
}
tour[i] = h3;
pos[h3] = i;
tour[n] = tour[0];
/* } */
}
} else {
fprintf(stderr,"this should never occur, 2-h-opt!!\n");
exit(0);
}
two_move = FALSE; node_move = FALSE;
} else {
dlb[c1] = TRUE;
}
}
}
free( random_vector );
free( dlb );
free( pos );
}
void three_opt_first( long int *tour )
/*
FUNCTION: 3-opt the tour
INPUT: pointer to the tour that is to optimize
OUTPUT: none
(SIDE)EFFECTS: tour is 3-opt
COMMENT: this is certainly not the best possible implementation of a 3-opt
local search algorithm. In addition, it is very lengthy; the main
reason herefore is that awkward way of making an exchange, where
it is tried to copy only the shortest possible part of a tour.
Whoever improves the code regarding speed or solution quality, please
drop me the code at stuetzle no@spam ulb.ac.be
The neighbourhood is scanned in random order (this need
not be the best possible choice). Concerning the speed-ups used
here consult, for example, Chapter 8 of
Holger H. Hoos and Thomas Stuetzle,
Stochastic Local Search---Foundations and Applications,
Morgan Kaufmann Publishers, 2004.
or some of the papers available online from David S. Johnson.
*/
{
/* In case a 2-opt move should be performed, we only need to store opt2_move = TRUE,
as h1, .. h4 are used in such a way that they store the indices of the correct move */
long int c1, c2, c3; /* cities considered for an exchange */
long int s_c1, s_c2, s_c3; /* successors of these cities */
long int p_c1, p_c2, p_c3; /* predecessors of these cities */
long int pos_c1, pos_c2, pos_c3; /* positions of cities c1, c2, c3 */
long int i, j, h, g, l;
long int improvement_flag, help;
long int h1=0, h2=0, h3=0, h4=0, h5=0, h6=0; /* memorize cities involved in a move */
long int diffs, diffp;
long int between = FALSE;
long int opt2_flag; /* = TRUE: perform 2-opt move, otherwise none or 3-opt move */
long int move_flag; /*
move_flag = 0 --> no 3-opt move
move_flag = 1 --> between_move (c3 between c1 and c2)
move_flag = 2 --> not_between with successors of c2 and c3
move_flag = 3 --> not_between with predecessors of c2 and c3
move_flag = 4 --> cyclic move
*/
long int gain, move_value, radius, add1, add2;
long int decrease_breaks; /* Stores decrease by breaking two edges (a,b) (c,d) */
long int val[3];
long int n1, n2, n3;
long int *pos; /* positions of cities in tour */
long int *dlb; /* vector containing don't look bits */
long int *h_tour; /* help vector for performing exchange move */
long int *hh_tour; /* help vector for performing exchange move */
long int *random_vector;
pos = malloc(n * sizeof(long int));
dlb = malloc(n * sizeof(long int));
h_tour = malloc(n * sizeof(long int));
hh_tour = malloc(n * sizeof(long int));
for ( i = 0 ; i < n ; i++ ) {
pos[tour[i]] = i;
dlb[i] = FALSE;
}
improvement_flag = TRUE;
random_vector = generate_random_permutation( n );
while ( improvement_flag ) {
move_value = 0;
improvement_flag = FALSE;
for ( l = 0 ; l < n ; l++ ) {
c1 = random_vector[l];
if ( dlb_flag && dlb[c1] )
continue;
opt2_flag = FALSE;
move_flag = 0;
pos_c1 = pos[c1];
s_c1 = tour[pos_c1+1];
if (pos_c1 > 0)
p_c1 = tour[pos_c1-1];
else
p_c1 = tour[n-1];
h = 0; /* Search for one of the h-nearest neighbours */
while ( h < nn_ls ) {
c2 = instance.nn_list[c1][h]; /* second city, determine its position */
pos_c2 = pos[c2];
s_c2 = tour[pos_c2+1];
if (pos_c2 > 0)
p_c2 = tour[pos_c2-1];
else
p_c2 = tour[n-1];
diffs = 0; diffp = 0;
radius = instance.distance[c1][s_c1];
add1 = instance.distance[c1][c2];
/* Here a fixed radius neighbour search is performed */
if ( radius > add1 ) {
decrease_breaks = - radius - instance.distance[c2][s_c2];
diffs = decrease_breaks + add1 + instance.distance[s_c1][s_c2];
diffp = - radius - instance.distance[c2][p_c2] +
instance.distance[c1][p_c2] + instance.distance[s_c1][c2];
}
else
break;
if ( p_c2 == c1 ) /* in case p_c2 == c1 no exchange is possible */
diffp = 0;
if ( (diffs < move_value) || (diffp < move_value) ) {
improvement_flag = TRUE;
if (diffs <= diffp) {
h1 = c1; h2 = s_c1; h3 = c2; h4 = s_c2;
move_value = diffs;
opt2_flag = TRUE; move_flag = 0;
/* goto exchange; */
} else {
h1 = c1; h2 = s_c1; h3 = p_c2; h4 = c2;
move_value = diffp;
opt2_flag = TRUE; move_flag = 0;
/* goto exchange; */
}
}
/* Now perform the innermost search */
g = 0;
while (g < nn_ls) {
c3 = instance.nn_list[s_c1][g];
pos_c3 = pos[c3];
s_c3 = tour[pos_c3+1];
if (pos_c3 > 0)
p_c3 = tour[pos_c3-1];
else
p_c3 = tour[n-1];
if ( c3 == c1 ) {
g++;
continue;
}
else {
add2 = instance.distance[s_c1][c3];
/* Perform fixed radius neighbour search for innermost search */
if ( decrease_breaks + add1 < add2 ) {
if ( pos_c2 > pos_c1 ) {
if ( pos_c3 <= pos_c2 && pos_c3 > pos_c1 )
between = TRUE;
else
between = FALSE;
}
else if ( pos_c2 < pos_c1 )
if ( pos_c3 > pos_c1 || pos_c3 < pos_c2 )
between = TRUE;
else
between = FALSE;
else {
printf(" Strange !!, pos_1 %ld == pos_2 %ld, \n",pos_c1,pos_c2);
}
if ( between ) {
/* We have to add edges (c1,c2), (c3,s_c1), (p_c3,s_c2) to get
valid tour; it's the only possibility */
gain = decrease_breaks - instance.distance[c3][p_c3] +
add1 + add2 +
instance.distance[p_c3][s_c2];
/* check for improvement by move */
if ( gain < move_value ) {
improvement_flag = TRUE; /* g = neigh_ls + 1; */
move_value = gain;
opt2_flag = FALSE;
move_flag = 1;
/* store nodes involved in move */
h1 = c1; h2 = s_c1; h3 = c2; h4 = s_c2; h5 = p_c3; h6 = c3;
goto exchange;
}
}
else { /* not between(pos_c1,pos_c2,pos_c3) */
/* We have to add edges (c1,c2), (s_c1,c3), (s_c2,s_c3) */
gain = decrease_breaks - instance.distance[c3][s_c3] +
add1 + add2 +
instance.distance[s_c2][s_c3];
if ( pos_c2 == pos_c3 ) {
gain = 20000;
}
/* check for improvement by move */
if ( gain < move_value ) {
improvement_flag = TRUE; /* g = neigh_ls + 1; */
move_value = gain;
opt2_flag = FALSE;
move_flag = 2;
/* store nodes involved in move */
h1 = c1; h2 = s_c1; h3 = c2; h4 = s_c2; h5 = c3; h6 = s_c3;
goto exchange;
}
/* or add edges (c1,c2), (s_c1,c3), (p_c2,p_c3) */
gain = - radius - instance.distance[p_c2][c2]
- instance.distance[p_c3][c3] +
add1 + add2 +
instance.distance[p_c2][p_c3];
if ( c3 == c2 || c2 == c1 || c1 == c3 || p_c2 == c1 ) {
gain = 2000000;
}
if ( gain < move_value ) {
improvement_flag = TRUE;
move_value = gain;
opt2_flag = FALSE;
move_flag = 3;
h1 = c1; h2 = s_c1; h3 = p_c2; h4 = c2; h5 = p_c3; h6 = c3;
goto exchange;
}
/* Or perform the 3-opt move where no subtour inversion is necessary
i.e. delete edges (c1,s_c1), (c2,p_c2), (c3,s_c3) and
add edges (c1,c2), (c3,s_c1), (p_c2,s_c3) */
gain = - radius - instance.distance[p_c2][c2] -
instance.distance[c3][s_c3]
+ add1 + add2 + instance.distance[p_c2][s_c3];
/* check for improvement */
if ( gain < move_value ) {
improvement_flag = TRUE;
move_value = gain;
opt2_flag = FALSE;
move_flag = 4;
improvement_flag = TRUE;
/* store nodes involved in move */
h1 = c1; h2 = s_c1; h3 = p_c2; h4 = c2; h5 = c3; h6 = s_c3;
goto exchange;
}
}
}
else
g = nn_ls + 1;
}
g++;
}
h++;
}
if ( move_flag || opt2_flag ) {
exchange:
move_value = 0;
/* Now make the exchange */
if ( move_flag ) {
dlb[h1] = FALSE; dlb[h2] = FALSE; dlb[h3] = FALSE;
dlb[h4] = FALSE; dlb[h5] = FALSE; dlb[h6] = FALSE;
pos_c1 = pos[h1]; pos_c2 = pos[h3]; pos_c3 = pos[h5];
if ( move_flag == 4 ) {
if ( pos_c2 > pos_c1 )
n1 = pos_c2 - pos_c1;
else
n1 = n - (pos_c1 - pos_c2);
if ( pos_c3 > pos_c2 )
n2 = pos_c3 - pos_c2;
else
n2 = n - (pos_c2 - pos_c3);
if ( pos_c1 > pos_c3 )
n3 = pos_c1 - pos_c3;
else
n3 = n - (pos_c3 - pos_c1);
/* n1: length h2 - h3, n2: length h4 - h5, n3: length h6 - h1 */
val[0] = n1; val[1] = n2; val[2] = n3;
/* Now order the partial tours */
h = 0;
help = LONG_MIN;
for ( g = 0; g <= 2; g++) {
if ( help < val[g] ) {
help = val[g];
h = g;
}
}
/* order partial tours according length */
if ( h == 0 ) {
/* copy part from pos[h4] to pos[h5]
direkt kopiert: Teil von pos[h6] to pos[h1], it
remains the part from pos[h2] to pos[h3] */
j = pos[h4];
h = pos[h5];
i = 0;
h_tour[i] = tour[j];
n1 = 1;
while ( j != h) {
i++;
j++;
if ( j >= n )
j = 0;
h_tour[i] = tour[j];
n1++;
}
/* First copy partial tour 3 in new position */
j = pos[h4];
i = pos[h6];
tour[j] = tour[i];
pos[tour[i]] = j;
while ( i != pos_c1) {
i++;
if ( i >= n )
i = 0;
j++;
if ( j >= n )
j = 0;
tour[j] = tour[i];
pos[tour[i]] = j;
}
/* Now copy stored part from h_tour */
j++;
if ( j >= n )
j = 0;
for ( i = 0; i<n1 ; i++ ) {
tour[j] = h_tour[i];
pos[h_tour[i]] = j;
j++;
if ( j >= n )
j = 0;
}
tour[n] = tour[0];
}
else if ( h == 1 ) {
/* copy part from pos[h6] to pos[h1]
direkt kopiert: Teil von pos[h2] to pos[h3], it
remains the part from pos[h4] to pos[h5] */
j = pos[h6];
h = pos[h1];
i = 0;
h_tour[i] = tour[j];
n1 = 1;
while ( j != h) {
i++;
j++;
if ( j >= n )
j = 0;
h_tour[i] = tour[j];
n1++;
}
/* First copy partial tour 3 in new position */
j = pos[h6];
i = pos[h2];
tour[j] = tour[i];
pos[tour[i]] = j;
while ( i != pos_c2) {
i++;
if ( i >= n )
i = 0;
j++;
if ( j >= n )
j = 0;
tour[j] = tour[i];
pos[tour[i]] = j;
}
/* Now copy stored part from h_tour */
j++;
if ( j >= n )
j = 0;
for ( i = 0; i<n1 ; i++ ) {
tour[j] = h_tour[i];
pos[h_tour[i]] = j;
j++;
if ( j >= n )
j = 0;
}
tour[n] = tour[0];
}
else if ( h == 2 ) {
/* copy part from pos[h2] to pos[h3]
direkt kopiert: Teil von pos[h4] to pos[h5], it
remains the part from pos[h6] to pos[h1] */
j = pos[h2];
h = pos[h3];
i = 0;
h_tour[i] = tour[j];
n1 = 1;
while ( j != h) {
i++;
j++;
if ( j >= n )
j = 0;
h_tour[i] = tour[j];
n1++;
}
/* First copy partial tour 3 in new position */
j = pos[h2];
i = pos[h4];
tour[j] = tour[i];
pos[tour[i]] = j;
while ( i != pos_c3) {
i++;
if ( i >= n )
i = 0;
j++;
if ( j >= n )
j = 0;
tour[j] = tour[i];
pos[tour[i]] = j;
}
/* Now copy stored part from h_tour */
j++;
if ( j >= n )
j = 0;
for ( i = 0; i<n1 ; i++ ) {
tour[j] = h_tour[i];
pos[h_tour[i]] = j;
j++;
if ( j >= n )
j = 0;
}
tour[n] = tour[0];
}
}
else if ( move_flag == 1 ) {
if ( pos_c3 < pos_c2 )
n1 = pos_c2 - pos_c3;
else
n1 = n - (pos_c3 - pos_c2);
if ( pos_c3 > pos_c1 )
n2 = pos_c3 - pos_c1 + 1;
else
n2 = n - (pos_c1 - pos_c3 + 1);
if ( pos_c2 > pos_c1 )
n3 = n - (pos_c2 - pos_c1 + 1);
else
n3 = pos_c1 - pos_c2 + 1;
/* n1: length h6 - h3, n2: length h5 - h2, n2: length h1 - h3 */
val[0] = n1; val[1] = n2; val[2] = n3;
/* Now order the partial tours */
h = 0;
help = LONG_MIN;
for ( g = 0; g <= 2; g++) {
if ( help < val[g] ) {
help = val[g];
h = g;
}
}
/* order partial tours according length */
if ( h == 0 ) {
/* copy part from pos[h5] to pos[h2]
(inverted) and from pos[h4] to pos[h1] (inverted)
it remains the part from pos[h6] to pos[h3] */
j = pos[h5];
h = pos[h2];
i = 0;
h_tour[i] = tour[j];
n1 = 1;
while ( j != h ) {
i++;
j--;
if ( j < 0 )
j = n-1;
h_tour[i] = tour[j];
n1++;
}
j = pos[h1];
h = pos[h4];
i = 0;
hh_tour[i] = tour[j];
n2 = 1;
while ( j != h) {
i++;
j--;
if ( j < 0 )
j = n-1;
hh_tour[i] = tour[j];
n2++;
}
j = pos[h4];
for ( i = 0; i< n2 ; i++ ) {
tour[j] = hh_tour[i];
pos[hh_tour[i]] = j;
j++;
if (j >= n)
j = 0;
}
/* Now copy stored part from h_tour */
for ( i = 0; i< n1 ; i++ ) {
tour[j] = h_tour[i];
pos[h_tour[i]] = j;
j++;
if ( j >= n )
j = 0;
}
tour[n] = tour[0];
}