TSP with random
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import java.awt.Graphics; | |
import java.awt.GridLayout; | |
import java.awt.image.BufferedImage; | |
import java.util.ArrayList; | |
import java.util.DoubleSummaryStatistics; | |
import java.util.List; | |
import java.util.Random; | |
import java.util.stream.Collectors; | |
import java.util.stream.IntStream; | |
import javax.swing.ImageIcon; | |
import javax.swing.JFrame; | |
import javax.swing.JLabel; | |
/** | |
* | |
* @author naoki | |
*/ | |
public class TSP { | |
public static void main(String[] args) { | |
JFrame f = new JFrame(); | |
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); | |
f.setSize(500, 400); | |
f.setLayout(new GridLayout(2, 1)); | |
Random r = new Random(1235); | |
int[] xs = r.ints(30, 0, 300).toArray(); | |
int[] ys = r.ints(30, 0, 300).toArray(); | |
//double solved = solve(xs, ys, 1, new int[xs.length]); | |
//System.out.println(solved); | |
BufferedImage route = new BufferedImage(320, 320, BufferedImage.TYPE_INT_RGB); | |
Graphics g = route.getGraphics(); | |
for(int i = 0; i < xs.length; ++i) { | |
g.drawRect(xs[i] + 9, ys[i] + 9, 3, 3); | |
} | |
f.add(new JLabel(new ImageIcon(route))); | |
int[] minRoute = null; | |
double min = Double.MAX_VALUE; | |
List<Double> hist = new ArrayList<>(); | |
for(int ii = 0; ii < 800000; ++ii){ | |
int[] gene = IntStream.range(0, xs.length).map(i -> r.nextInt(xs.length - i)).toArray(); | |
List<Integer> list = IntStream.range(0, xs.length).boxed().collect(Collectors.toList()); | |
int[] rt = IntStream.of(gene).map(list::remove).toArray(); | |
double d = 0; | |
for(int i = 0; i < rt.length; ++i){ | |
int j = (i + 1) % rt.length; | |
d += Math.sqrt((xs[rt[i]] - xs[rt[j]]) * (xs[rt[i]] - xs[rt[j]]) + | |
(ys[rt[i]] - ys[rt[j]]) * (ys[rt[i]] - ys[rt[j]])); | |
} | |
if(d < min) { | |
min = d; | |
minRoute = rt; | |
} | |
hist.add(min); | |
} | |
System.out.println(min); | |
for(int i = 0; i < minRoute.length; ++i){ | |
int j = (i + 1) % minRoute.length; | |
g.drawLine(xs[minRoute[i]] + 10, ys[minRoute[i]] + 10, xs[minRoute[j]] + 10, ys[minRoute[j]] + 10); | |
} | |
DoubleSummaryStatistics st = hist.stream().mapToDouble(d -> d).summaryStatistics(); | |
BufferedImage img = new BufferedImage(500, 300, BufferedImage.TYPE_INT_RGB); | |
Graphics gg = img.getGraphics(); | |
double solved = st.getMin(); | |
double range = st.getMax() - solved; | |
gg.drawLine(20, 275, 470, 275); | |
for(int i = 1; i < hist.size(); ++i){ | |
int y1 = (int)((hist.get(i - 1) - solved) / range * 250); | |
int y2 = (int)((hist.get(i) - solved) / range * 250); | |
gg.drawLine(i * 450 / hist.size() + 20, 275 - y1, (i + 1) * 450 / hist.size() + 20, 275 - y2); | |
} | |
f.add(new JLabel(new ImageIcon(img))); | |
f.setVisible(true); | |
} | |
/* | |
static double solve(int[] xs, int[] ys, int idx, int[] root){ | |
if(idx >= root.length) { | |
List<Integer> list = IntStream.range(0, root.length).boxed().collect(Collectors.toList()); | |
int[] rt = IntStream.of(root).map(list::remove).toArray(); | |
double d = 0; | |
for(int i = 0; i < rt.length; ++i){ | |
int j = (i + 1) % rt.length; | |
d += Math.sqrt((xs[rt[i]] - xs[rt[j]]) * (xs[rt[i]] - xs[rt[j]]) + | |
(ys[rt[i]] - ys[rt[j]]) * (ys[rt[i]] - ys[rt[j]])); | |
} | |
return d; | |
} | |
double min = Double.MAX_VALUE; | |
for(int i = 0; i < root.length - idx; ++i){ | |
root[idx] = i; | |
double d = solve(xs, ys, idx + 1, root); | |
if (d < min){ | |
min = d; | |
} | |
} | |
return min; | |
}*/ | |
} |
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kishida commentedFeb 5, 2016