001
002
003
004
005
006
007
008
009
010
011
012
013
014
015
016
017
018
019
020
021
022
023
024
025
026
027
028
029
030
031
032
033
034
035
036
037
038
039
040
041
042
043
044
045
046
047
048
049
050
051
052
053
054
055
056
057
058
059
060
061
062
063
064
065
066
067
068
069
070
071
072
073
074
075
076
077
078
079
080
081
082
083
084
085
086
087
088
089
090
091
092
093
094
095
096
097
098
099
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
package agent.four;
public class Main {
public static void main (String[] args) {
World w = WorldF.instance(100,100);
int i = 0;
while (i<20) {
try {
new Tiger
(Integer.toString(i), Util.random(w.maxx()), Util.random(w.maxy()));
i++;
} catch (SpaceOccupiedException e) {
}
}
w.run(1000);
}
}
class Util {
private Util() {}
private final static long SEED = 2497;
private final static java.util.Random r = new java.util.Random(SEED);
static int random(int n) { return r.nextInt(n); }
static boolean randomBoolean() { return r.nextBoolean(); }
}
interface World extends TimeServer {
public int maxx();
public int maxy();
public Visible get(int i, int j);
public boolean set(int i, int j, Visible a);
}
class WorldF {
private static World W;
public static World instance(int maxx, int maxy) {
if (W != null)
throw new IllegalStateException();
W = new WorldObj(maxx, maxy);
return W;
}
public static World instance() {
if (W == null)
throw new IllegalStateException();
return W;
}
}
class WorldObj implements World {
private final int maxx;
private final int maxy;
private final TimeServer time;
private final Visible[][] space;
WorldObj(int maxx, int maxy) {
this.maxx = maxx;
this.maxy = maxy;
time = new TimeServerLinked();
space = new Visible[maxx][maxy];
for (int x = 0; x < maxx; x++ )
for (int y = 0; y < maxy; y++ )
space[x][y] = NullVisible.instance;
}
public int maxx() { return maxx; }
public int maxy() { return maxy; }
public Visible get(int x, int y) {
return space[(x+maxx)%maxx][(y+maxy)%maxy];
}
public boolean set(int x, int y, Visible a){
if (a == null) {
a = NullVisible.instance;
} else if (get(x,y) != NullVisible.instance) {
return false;
}
space[(x+maxx)%maxx][(y+maxy)%maxy] = a;
return true;
}
public long currentTime() { return time.currentTime(); }
public void enqueue(long t, Agent a) { time.enqueue(t,a); }
public void run(int d) { time.run(d); }
}
interface Visible {
public final static int NULL = 0;
public final static int TIGER = 1;
public int type();
}
class NullVisible implements Visible {
private NullVisible() {}
public final static Visible instance = new NullVisible();
public int type() { return Visible.NULL; }
public String toString() { return "Null"; }
}
class SpaceOccupiedException extends RuntimeException {
private static final long serialVersionUID = 2008L;
};
class Tiger implements Agent, Visible {
private String name;
private int x;
private int y;
private World w = WorldF.instance();
public Tiger(String name, int x, int y)
throws SpaceOccupiedException
{
this.name = name;
if (!w.set(x,y,this))
throw new SpaceOccupiedException();
this.x = x;
this.y = y;
w.enqueue(1+w.currentTime(), this);
}
public String toString() { return name + "@(" + x + "," + y + ")"; }
public int type() { return Visible.TIGER; }
public void check() {
checkAjacent();
}
public void run() {
//System.out.print(this + " moves to ");
moveRandom();
//System.out.println(this);
w.enqueue(10+w.currentTime(), this);
}
private void checkAjacent() {
for (int i=-1; i<=1; i++) {
for (int j=-1; j<=1; j++) {
if (i==0 && j==0)
continue;
if (w.get(x+i,y+j).type() == Visible.TIGER)
System.out.println(this + " roars at " + w.get(x+i,y+j) + " at " + w.currentTime());
}
}
}
private void moveRandom() {
w.set(x,y,null);
int xNew, yNew;
do {
xNew = (w.maxx() + this.x -1 + Util.random(2)) % w.maxx();
yNew = (w.maxy() + this.y -1 + Util.random(2)) % w.maxy();
//System.out.println("Trying (" + x + "," + y + ")");
} while (!w.set(xNew,yNew,this));
this.x = xNew; this.y = yNew;
}
}
|
