int[] improve_routes_2opt(int[] sol) {
int[] res;
int[][] routes = get_routes(sol);
for (int i = 0; i < routes.length; i++) if (routes[i].length > 2) tspp.one_pass_2opt(routes[i]);
res = routes_to_array(routes);
return res;
}
// String exchange move - only when improves
// returns cost of new solution
// mode = ALWAYS_PERFORM ou PERFORM_ON_IMPROVE
double string_exchange(
int[][] routes,
int r1,
int r2,
int x1,
int x2,
int c1,
int c2,
int mode,
boolean feasible,
boolean sw) {
int[] newr1;
int[] newr2;
int i, j, k;
double res;
newr1 = new int[routes[r1].length - x1 + x2];
newr2 = new int[routes[r2].length - x2 + x1];
for (i = 0, k = 0; i < c1; i++, k++) newr1[k] = routes[r1][i];
for (j = c2; j < c2 + x2; j++, k++) newr1[k] = routes[r2][j];
for (; i < c1 + x1; i++) ;
for (; i < routes[r1].length; i++, k++) newr1[k] = routes[r1][i];
for (i = 0, k = 0; i < c2; i++, k++) newr2[k] = routes[r2][i];
for (j = c1; j < c1 + x1; j++, k++) newr2[k] = routes[r1][j];
for (; i < c2 + x2; i++) ;
for (; i < routes[r2].length; i++, k++) newr2[k] = routes[r2][i];
if (!feasible) {
double oldpen = excess_demand_route(routes[r1]) + excess_demand_route(routes[r2]);
double newpen = excess_demand_route(newr1) + excess_demand_route(newr2);
if (mode == ALWAYS_PERFORM || newpen < oldpen) {
if (sw) {
routes[r1] = newr1;
routes[r2] = newr2;
}
res = oldpen - newpen;
} else res = 0.0;
} else {
double newpen = excess_demand_route(newr1) + excess_demand_route(newr2);
if (newpen > 0.0 && mode != ALWAYS_PERFORM) res = 0.0;
else {
double oldcost = tspp.cost(routes[r1]) + tspp.cost(routes[r2]);
tspp.one_pass_2opt(newr1);
tspp.one_pass_2opt(newr2);
double newcost = tspp.cost(newr1) + tspp.cost(newr2);
if (mode == ALWAYS_PERFORM || oldcost > newcost) {
if (sw) {
routes[r1] = newr1;
routes[r2] = newr2;
}
res = oldcost - newcost;
} else res = 0.0;
}
}
return res;
}
// String cross move - only perform if there is improvement
// returns improvement
// if sw is true perform the switch when solution is better else only return value
// mode = ALWAYS_PERFORM ou PERFORM_ON_IMPROVE
double string_cross(
int[][] routes, int r1, int r2, int c1, int c2, int mode, boolean feasible, boolean sw) {
double res;
int[] newr1;
int[] newr2;
int i, j;
newr1 = new int[c1 + (routes[r2].length - c2)];
newr2 = new int[c2 + (routes[r1].length - c1)];
for (i = 0; i < c1; i++) newr1[i] = routes[r1][i];
for (j = c2; j < routes[r2].length; j++, i++) newr1[i] = routes[r2][j];
for (i = 0; i < c2; i++) newr2[i] = routes[r2][i];
for (j = c1; j < routes[r1].length; j++, i++) newr2[i] = routes[r1][j];
if (!feasible) {
double oldpen = excess_demand_route(routes[r1]) + excess_demand_route(routes[r2]);
double newpen = excess_demand_route(newr1) + excess_demand_route(newr2);
if (mode == ALWAYS_PERFORM || newpen < oldpen) {
if (sw) {
routes[r1] = newr1;
routes[r2] = newr2;
}
res = oldpen - newpen;
} else res = 0.0;
} else {
double newpen = excess_demand_route(newr1) + excess_demand_route(newr2);
if (newpen > 0.0 && mode != ALWAYS_PERFORM) res = 0.0;
else {
double oldcost = tspp.cost(routes[r1]) + tspp.cost(routes[r2]);
tspp.one_pass_2opt(newr1);
tspp.one_pass_2opt(newr2);
double newcost = tspp.cost(newr1) + tspp.cost(newr2);
if (mode == ALWAYS_PERFORM || oldcost > newcost) {
if (sw) {
routes[r1] = newr1;
routes[r2] = newr2;
}
res = oldcost - newcost;
} else res = 0.0;
}
}
return res;
}
void improve_routes_2opt(int[][] routes) {
for (int i = 0; i < routes.length; i++) {
tspp.one_pass_2opt(routes[i]);
}
}