forked from ckcz123/codejam
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathB.java
More file actions
162 lines (151 loc) · 5.31 KB
/
Copy pathB.java
File metadata and controls
162 lines (151 loc) · 5.31 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
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
151
152
153
154
155
156
157
158
159
160
161
162
import java.io.PrintStream;
import java.util.*;
/**
* Codejam 2012 Round 3
* Problem B. Havannah
*/
public class Main {
class UnionFind {
int[] father;
int s;
UnionFind(int _s) {
s=_s;
father=new int[4*s*s];
for (int i=0;i<4*s*s;i++) father[i]=i;
}
private int findfather(int x) {
return father[x]==x?x:(father[x]=findfather(father[x]));
}
void link(int x1, int y1, int x2, int y2) {
link(encode(x1,y1), encode(x2,y2));
}
private void link(int x, int y) {
father[findfather(x)]=findfather(y);
}
boolean linked(int x1, int y1, int x2, int y2) {
return linked(encode(x1,y1), encode(x2,y2));
}
private boolean linked(int x, int y) {
return findfather(x)==findfather(y);
}
private int encode(int x, int y) {
return x*(2*s)+y;
}
}
public String solve(Scanner scanner) {
int s=scanner.nextInt(), m=scanner.nextInt();
boolean[][] map=new boolean[2*s][2*s];
UnionFind unionFind =new UnionFind(s);
int[][] corners=new int[][] {{1,1},{1,s},{s,1},{2*s-1,s},{s,2*s-1},{2*s-1,2*s-1}};
int[][][] edges=new int[6][s-2][2];
for (int i=2;i<s;i++) {
edges[0][i-2]=new int[]{1,i};
edges[1][i-2]=new int[]{i,1};
edges[2][i-2]=new int[]{i,i+s-1};
edges[3][i-2]=new int[]{i+s-1,i};
edges[4][i-2]=new int[]{2*s-1,2*s-i};
edges[5][i-2]=new int[]{2*s-i,2*s-1};
}
int[][] input=new int[m][2];
for (int i=0;i<m;i++)
input[i]=new int[] {scanner.nextInt(), scanner.nextInt()};
for (int i=0;i<m;i++) {
int x=input[i][0], y=input[i][1];
boolean isRing=testRing(s, map, unionFind, x, y);
map[x][y]=true;
for (int[] adj: adjancent(s, map, x, y)) {
unionFind.link(x,y,adj[0],adj[1]);
}
ArrayList<String> list=new ArrayList<>();
if (testBridge(corners, unionFind, x, y)) list.add("bridge");
if (testFork(edges, unionFind, x, y)) list.add("fork");
if (isRing) list.add("ring");
if (!list.isEmpty())
return String.format("%s in move %d", String.join("-", list), i+1);
}
return "none";
}
private boolean testRing(int s, boolean[][] map, UnionFind unionFind, int x, int y) {
ArrayList<int[]> adj=adjancent(s,map,x,y);
int n=adj.size();
if (n<2) return false;
boolean[][] linked=new boolean[n][n];
for (int i=0;i<n;i++) {
linked[i][i]=true;
for (int j=0;j<n;j++) {
int[] u=adj.get(i), v=adj.get(j);
int dx=u[0]-v[0], dy=u[1]-v[1];
if (Math.abs(dx)<=1 && Math.abs(dy)<=1 && dx+dy!=0)
linked[i][j]=linked[j][i]=true;
}
}
for (int k=0;k<n;k++) {
for (int i=0;i<n;i++) {
for (int j=0;j<n;j++) {
if (linked[i][k] && linked[k][j]) linked[i][j]=true;
}
}
}
for (int i=0;i<n;i++) {
for (int j=0;j<n;j++) {
int[] u=adj.get(i), v=adj.get(j);
if (!linked[i][j] && unionFind.linked(u[0],u[1],v[0],v[1]))
return true;
}
}
return false;
}
private boolean testBridge(int[][] corners, UnionFind unionFind, int x, int y) {
int cnt=0;
for (int[] c: corners) {
if (unionFind.linked(c[0],c[1],x,y))
cnt++;
}
return cnt>=2;
}
private boolean testFork(int[][][] edges, UnionFind unionFind, int x, int y) {
int cnt=0;
for (int[][] edge: edges) {
boolean is=false;
for (int[] e: edge) {
if (unionFind.linked(e[0],e[1],x,y)) {
is=true;break;
}
}
if (is) cnt++;
}
return cnt>=3;
}
private ArrayList<int[]> adjancent(int s, boolean[][] map, int x, int y) {
ArrayList<int[]> list=new ArrayList<>();
for (int dx=-1;dx<=1;dx++) {
for (int dy=-1;dy<=1;dy++) {
if (dx+dy==0) continue;
int nx=x+dx, ny=y+dy;
if (!valid(nx,ny,s)) continue;
if (map[nx][ny]) list.add(new int[]{nx,ny});
}
}
return list;
}
private boolean valid(int x, int y, int s) {
return x>=1 && y>=1 && x<2*s && y<2*s && Math.abs(x-y)<=s-1;
}
public static void main(String[] args) throws Exception {
System.setOut(new PrintStream("output.txt"));
Scanner scanner=new Scanner(System.in);
int times=scanner.nextInt();
long start=System.currentTimeMillis();
for (int t=1;t<=times;t++) {
try {
System.out.println(String.format("Case #%d: %s", t, new Main().solve(scanner)));
}
catch (Throwable e) {
System.err.println("ERROR in case #"+t);
e.printStackTrace();
}
}
long end=System.currentTimeMillis();
System.err.println(String.format("Time used: %.3fs", (end-start)/1000.0));
}
}