oj.uz

Submission #339249

# Submission time Handle Problem Language Result Execution time Memory
339249 2020-12-25T00:34:25 Z KWang31 Mergers (JOI19_mergers) Java 11
70 / 100
 3000 ms 143524 KB 
import java.io.*; import java.util.*;
public class mergers{
  static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
        String next() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        
    } 
    public static class Pair implements Comparable<Pair>{
        int vtx; int val;
        public Pair(int a, int b){
            this.vtx=a; this.val=b;
        }
        public int compareTo(Pair other){
            if(this.val<other.val)return -1;
            if(this.val>other.val)return 1;
            if(this.vtx<other.vtx)return -1;
            return 1;
        }
    }
    static int MOD=998244353;
    static int[] rk, p,siz;
    static int[] par,dep;
    public static void main(String[] args){
        FastReader br=new FastReader();
        int N=br.nextInt(); int M=br.nextInt();
        ArrayList<Integer> states[]=new ArrayList[M]; for(int i=0;i<M;i++){states[i]=new ArrayList<>();}
        ArrayList<Integer> adj[]=new ArrayList[N]; for(int i=0;i<N;i++){adj[i]=new ArrayList<>();}
        int a,b;
        for (int i = 0; i < N-1; i++) {
            a=br.nextInt()-1; b=br.nextInt()-1; adj[a].add(b); adj[b].add(a);
        }
        for (int i = 0; i < N; i++) {
            a=br.nextInt()-1; states[a].add(i);
        }
        par=new int[N]; dep=new int[N]; dfs(adj,-1,0);
        
        int[] skip=new int[N];//Skipping: avoiding repeated merging
        for (int i = 0; i < N; i++) {
            skip[i]=i;
        }
        
        for (int i = 0; i < M; i++) {
            if(states[i].isEmpty())continue;
            
            for (int j = 0; j < states[i].size()-1; j++) {
                a=states[i].get(j); b=states[i].get(j+1);
                
                while(a!=b){
                    if(dep[a]>=dep[b]){
                        skip[a]=find(par[a],skip); a=skip[a]; 
                    }else{
                        skip[b]=find(par[b],skip); b=skip[b]; 
                    }
                }
                //For each a, we have merged a with its 1st, .., kth ancestor.
                //They belong to the same state
            }
        }
        //In the end, all vertices of the same state have the same skip
        //Therefore, after merging, if two vertices don't have some skip, they are not in the same state
        int[] deg=new int[N];
        
        for (int i = 0; i < N; i++) {
            a=find(i,skip);
            for (int j : adj[i]) {
                if(a!=find(j,skip)){
                    //Notice in the compressed form, there is only one leader for each state, namely j
                    //If i is adjacent to two vertices with same find, i must have that find too
                    deg[a]++;
                }
            }
        }
        //System.out.println(Arrays.toString(deg));
        int ans=0;
        for (int i = 0; i < N; i++) {
            if(deg[i]==1)ans++;
        }
        System.out.println((ans+1)/2);
        //If a state is a leaf, there exist exactly one 
    }
    
    public static int find(int x, int[] p){
        if(p[x]==x)return x;
        p[x]=find(p[x],p); return p[x];
    }
    
    public static void merge(int a, int b) {
        if(rk[a]<rk[b]) {
            p[a]=b; siz[b]+=siz[a];
        }else if(rk[a]==rk[b]) {
            p[a]=b; rk[b]++;siz[b]+=siz[a];
        }else {
            p[b]=a; siz[a]+=siz[b];
        }
    }
    public static void dfs(ArrayList<Integer>[] adj, int p, int v){
        for (int c : adj[v]) {
            if(c==p)continue;
            dep[c]=dep[v]+1; par[c]=v; dfs(adj,v,c);
        }
    }
}
//Debugging:
//Are you sure your algorithm is correct?
//Bounds: long
//Special cases: n=0,1?
//Make sure you remove your debugging code before you submit!

Compilation message

Note: mergers.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 72 ms 8556 KB Output is correct
2 Correct 76 ms 8448 KB Output is correct
3 Correct 77 ms 8520 KB Output is correct
4 Correct 71 ms 8512 KB Output is correct
5 Correct 72 ms 8556 KB Output is correct
6 Correct 76 ms 8556 KB Output is correct
7 Correct 70 ms 8684 KB Output is correct
8 Correct 76 ms 8448 KB Output is correct
9 Correct 70 ms 8556 KB Output is correct
10 Correct 70 ms 8556 KB Output is correct
11 Correct 77 ms 8448 KB Output is correct
12 Correct 74 ms 8428 KB Output is correct
13 Correct 74 ms 8556 KB Output is correct
14 Correct 76 ms 8556 KB Output is correct
15 Correct 78 ms 8556 KB Output is correct
16 Correct 70 ms 8556 KB Output is correct
17 Correct 71 ms 8556 KB Output is correct
18 Correct 77 ms 8556 KB Output is correct
19 Correct 71 ms 8556 KB Output is correct
20 Correct 72 ms 8684 KB Output is correct
21 Correct 76 ms 8556 KB Output is correct
22 Correct 76 ms 8576 KB Output is correct
23 Correct 71 ms 8556 KB Output is correct
24 Correct 73 ms 8556 KB Output is correct

Subtask #2
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 72 ms 8556 KB Output is correct
2 Correct 76 ms 8448 KB Output is correct
3 Correct 77 ms 8520 KB Output is correct
4 Correct 71 ms 8512 KB Output is correct
5 Correct 72 ms 8556 KB Output is correct
6 Correct 76 ms 8556 KB Output is correct
7 Correct 70 ms 8684 KB Output is correct
8 Correct 76 ms 8448 KB Output is correct
9 Correct 70 ms 8556 KB Output is correct
10 Correct 70 ms 8556 KB Output is correct
11 Correct 77 ms 8448 KB Output is correct
12 Correct 74 ms 8428 KB Output is correct
13 Correct 74 ms 8556 KB Output is correct
14 Correct 76 ms 8556 KB Output is correct
15 Correct 78 ms 8556 KB Output is correct
16 Correct 70 ms 8556 KB Output is correct
17 Correct 71 ms 8556 KB Output is correct
18 Correct 77 ms 8556 KB Output is correct
19 Correct 71 ms 8556 KB Output is correct
20 Correct 72 ms 8684 KB Output is correct
21 Correct 76 ms 8556 KB Output is correct
22 Correct 76 ms 8576 KB Output is correct
23 Correct 71 ms 8556 KB Output is correct
24 Correct 73 ms 8556 KB Output is correct
25 Correct 74 ms 8556 KB Output is correct
26 Correct 288 ms 14560 KB Output is correct
27 Correct 286 ms 14432 KB Output is correct
28 Correct 288 ms 15056 KB Output is correct
29 Correct 287 ms 14684 KB Output is correct
30 Correct 290 ms 14540 KB Output is correct
31 Correct 76 ms 8552 KB Output is correct
32 Correct 288 ms 14688 KB Output is correct
33 Correct 74 ms 8684 KB Output is correct
34 Correct 287 ms 14684 KB Output is correct
35 Correct 288 ms 14816 KB Output is correct
36 Correct 288 ms 14548 KB Output is correct
37 Correct 288 ms 14560 KB Output is correct
38 Correct 77 ms 8556 KB Output is correct
39 Correct 323 ms 14668 KB Output is correct
40 Correct 334 ms 14556 KB Output is correct
41 Correct 286 ms 14660 KB Output is correct
42 Correct 287 ms 14792 KB Output is correct
43 Correct 285 ms 14944 KB Output is correct
44 Correct 77 ms 8556 KB Output is correct
45 Correct 339 ms 14964 KB Output is correct
46 Correct 335 ms 14792 KB Output is correct
47 Correct 76 ms 8556 KB Output is correct
48 Correct 283 ms 14452 KB Output is correct
49 Correct 287 ms 14692 KB Output is correct
50 Correct 287 ms 14800 KB Output is correct
51 Correct 289 ms 14560 KB Output is correct
52 Correct 288 ms 14592 KB Output is correct
53 Correct 285 ms 14560 KB Output is correct
54 Correct 287 ms 14560 KB Output is correct

Subtask #3
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 72 ms 8556 KB Output is correct
2 Correct 76 ms 8448 KB Output is correct
3 Correct 77 ms 8520 KB Output is correct
4 Correct 71 ms 8512 KB Output is correct
5 Correct 72 ms 8556 KB Output is correct
6 Correct 76 ms 8556 KB Output is correct
7 Correct 70 ms 8684 KB Output is correct
8 Correct 76 ms 8448 KB Output is correct
9 Correct 70 ms 8556 KB Output is correct
10 Correct 70 ms 8556 KB Output is correct
11 Correct 77 ms 8448 KB Output is correct
12 Correct 74 ms 8428 KB Output is correct
13 Correct 74 ms 8556 KB Output is correct
14 Correct 76 ms 8556 KB Output is correct
15 Correct 78 ms 8556 KB Output is correct
16 Correct 70 ms 8556 KB Output is correct
17 Correct 71 ms 8556 KB Output is correct
18 Correct 77 ms 8556 KB Output is correct
19 Correct 71 ms 8556 KB Output is correct
20 Correct 72 ms 8684 KB Output is correct
21 Correct 76 ms 8556 KB Output is correct
22 Correct 76 ms 8576 KB Output is correct
23 Correct 71 ms 8556 KB Output is correct
24 Correct 73 ms 8556 KB Output is correct
25 Correct 73 ms 8556 KB Output is correct
26 Correct 724 ms 34964 KB Output is correct
27 Correct 717 ms 35464 KB Output is correct
28 Correct 287 ms 14452 KB Output is correct
29 Correct 73 ms 8428 KB Output is correct
30 Correct 73 ms 8556 KB Output is correct
31 Correct 725 ms 35124 KB Output is correct
32 Correct 285 ms 14400 KB Output is correct
33 Correct 786 ms 40548 KB Output is correct
34 Correct 790 ms 36536 KB Output is correct
35 Correct 287 ms 14624 KB Output is correct
36 Correct 779 ms 37856 KB Output is correct
37 Correct 337 ms 14800 KB Output is correct
38 Correct 282 ms 14544 KB Output is correct
39 Correct 680 ms 37052 KB Output is correct
40 Correct 285 ms 14876 KB Output is correct
41 Correct 722 ms 36708 KB Output is correct
42 Correct 1008 ms 39192 KB Output is correct
43 Correct 79 ms 8684 KB Output is correct
44 Correct 747 ms 42020 KB Output is correct
45 Correct 758 ms 39964 KB Output is correct
46 Correct 290 ms 14560 KB Output is correct
47 Correct 286 ms 14688 KB Output is correct

Subtask #4
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 704 ms 34940 KB Output is correct
2 Correct 751 ms 47956 KB Output is correct
3 Correct 289 ms 14560 KB Output is correct
4 Correct 286 ms 14724 KB Output is correct
5 Correct 72 ms 8556 KB Output is correct
6 Correct 74 ms 8556 KB Output is correct
7 Correct 303 ms 14552 KB Output is correct
8 Correct 764 ms 37044 KB Output is correct
9 Correct 289 ms 14688 KB Output is correct
10 Correct 760 ms 34948 KB Output is correct
11 Correct 78 ms 8680 KB Output is correct
12 Correct 741 ms 35300 KB Output is correct
13 Correct 754 ms 37376 KB Output is correct
14 Correct 830 ms 41856 KB Output is correct
15 Correct 684 ms 35532 KB Output is correct
16 Correct 292 ms 14560 KB Output is correct
17 Correct 77 ms 8556 KB Output is correct
18 Correct 756 ms 47224 KB Output is correct
19 Correct 1205 ms 50508 KB Output is correct
20 Correct 346 ms 14480 KB Output is correct
21 Correct 78 ms 8556 KB Output is correct
22 Correct 765 ms 39864 KB Output is correct
23 Correct 287 ms 14684 KB Output is correct
24 Correct 723 ms 35556 KB Output is correct
25 Correct 761 ms 44432 KB Output is correct
26 Correct 288 ms 14808 KB Output is correct
27 Correct 293 ms 14800 KB Output is correct
28 Correct 290 ms 14612 KB Output is correct
29 Correct 291 ms 14688 KB Output is correct
30 Correct 286 ms 14800 KB Output is correct

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 72 ms 8556 KB Output is correct
2 Correct 76 ms 8448 KB Output is correct
3 Correct 77 ms 8520 KB Output is correct
4 Correct 71 ms 8512 KB Output is correct
5 Correct 72 ms 8556 KB Output is correct
6 Correct 76 ms 8556 KB Output is correct
7 Correct 70 ms 8684 KB Output is correct
8 Correct 76 ms 8448 KB Output is correct
9 Correct 70 ms 8556 KB Output is correct
10 Correct 70 ms 8556 KB Output is correct
11 Correct 77 ms 8448 KB Output is correct
12 Correct 74 ms 8428 KB Output is correct
13 Correct 74 ms 8556 KB Output is correct
14 Correct 76 ms 8556 KB Output is correct
15 Correct 78 ms 8556 KB Output is correct
16 Correct 70 ms 8556 KB Output is correct
17 Correct 71 ms 8556 KB Output is correct
18 Correct 77 ms 8556 KB Output is correct
19 Correct 71 ms 8556 KB Output is correct
20 Correct 72 ms 8684 KB Output is correct
21 Correct 76 ms 8556 KB Output is correct
22 Correct 76 ms 8576 KB Output is correct
23 Correct 71 ms 8556 KB Output is correct
24 Correct 73 ms 8556 KB Output is correct
25 Correct 74 ms 8556 KB Output is correct
26 Correct 288 ms 14560 KB Output is correct
27 Correct 286 ms 14432 KB Output is correct
28 Correct 288 ms 15056 KB Output is correct
29 Correct 287 ms 14684 KB Output is correct
30 Correct 290 ms 14540 KB Output is correct
31 Correct 76 ms 8552 KB Output is correct
32 Correct 288 ms 14688 KB Output is correct
33 Correct 74 ms 8684 KB Output is correct
34 Correct 287 ms 14684 KB Output is correct
35 Correct 288 ms 14816 KB Output is correct
36 Correct 288 ms 14548 KB Output is correct
37 Correct 288 ms 14560 KB Output is correct
38 Correct 77 ms 8556 KB Output is correct
39 Correct 323 ms 14668 KB Output is correct
40 Correct 334 ms 14556 KB Output is correct
41 Correct 286 ms 14660 KB Output is correct
42 Correct 287 ms 14792 KB Output is correct
43 Correct 285 ms 14944 KB Output is correct
44 Correct 77 ms 8556 KB Output is correct
45 Correct 339 ms 14964 KB Output is correct
46 Correct 335 ms 14792 KB Output is correct
47 Correct 76 ms 8556 KB Output is correct
48 Correct 283 ms 14452 KB Output is correct
49 Correct 287 ms 14692 KB Output is correct
50 Correct 287 ms 14800 KB Output is correct
51 Correct 289 ms 14560 KB Output is correct
52 Correct 288 ms 14592 KB Output is correct
53 Correct 285 ms 14560 KB Output is correct
54 Correct 287 ms 14560 KB Output is correct
55 Correct 73 ms 8556 KB Output is correct
56 Correct 724 ms 34964 KB Output is correct
57 Correct 717 ms 35464 KB Output is correct
58 Correct 287 ms 14452 KB Output is correct
59 Correct 73 ms 8428 KB Output is correct
60 Correct 73 ms 8556 KB Output is correct
61 Correct 725 ms 35124 KB Output is correct
62 Correct 285 ms 14400 KB Output is correct
63 Correct 786 ms 40548 KB Output is correct
64 Correct 790 ms 36536 KB Output is correct
65 Correct 287 ms 14624 KB Output is correct
66 Correct 779 ms 37856 KB Output is correct
67 Correct 337 ms 14800 KB Output is correct
68 Correct 282 ms 14544 KB Output is correct
69 Correct 680 ms 37052 KB Output is correct
70 Correct 285 ms 14876 KB Output is correct
71 Correct 722 ms 36708 KB Output is correct
72 Correct 1008 ms 39192 KB Output is correct
73 Correct 79 ms 8684 KB Output is correct
74 Correct 747 ms 42020 KB Output is correct
75 Correct 758 ms 39964 KB Output is correct
76 Correct 290 ms 14560 KB Output is correct
77 Correct 286 ms 14688 KB Output is correct
78 Correct 704 ms 34940 KB Output is correct
79 Correct 751 ms 47956 KB Output is correct
80 Correct 289 ms 14560 KB Output is correct
81 Correct 286 ms 14724 KB Output is correct
82 Correct 72 ms 8556 KB Output is correct
83 Correct 74 ms 8556 KB Output is correct
84 Correct 303 ms 14552 KB Output is correct
85 Correct 764 ms 37044 KB Output is correct
86 Correct 289 ms 14688 KB Output is correct
87 Correct 760 ms 34948 KB Output is correct
88 Correct 78 ms 8680 KB Output is correct
89 Correct 741 ms 35300 KB Output is correct
90 Correct 754 ms 37376 KB Output is correct
91 Correct 830 ms 41856 KB Output is correct
92 Correct 684 ms 35532 KB Output is correct
93 Correct 292 ms 14560 KB Output is correct
94 Correct 77 ms 8556 KB Output is correct
95 Correct 756 ms 47224 KB Output is correct
96 Correct 1205 ms 50508 KB Output is correct
97 Correct 346 ms 14480 KB Output is correct
98 Correct 78 ms 8556 KB Output is correct
99 Correct 765 ms 39864 KB Output is correct
100 Correct 287 ms 14684 KB Output is correct
101 Correct 723 ms 35556 KB Output is correct
102 Correct 761 ms 44432 KB Output is correct
103 Correct 288 ms 14808 KB Output is correct
104 Correct 293 ms 14800 KB Output is correct
105 Correct 290 ms 14612 KB Output is correct
106 Correct 291 ms 14688 KB Output is correct
107 Correct 286 ms 14800 KB Output is correct
108 Correct 2037 ms 141652 KB Output is correct
109 Correct 2140 ms 143524 KB Output is correct
110 Execution timed out 3088 ms 140680 KB Time limit exceeded
111 Halted 0 ms 0 KB -