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답안 #630993

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
630993 2022-08-17T12:21:41 Z bachhoangxuan Cat in a tree (BOI17_catinatree) C++17
100 / 100
 366 ms 72560 KB 
#include<bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define maxn 400005
#define maxl 25
const int inf=1e9;
int n,d,depth[maxn],Min[maxn][maxl],L[maxn],len,logx[maxn];
int dad[maxn],res[maxn],child[maxn],sz;
bool used[maxn];
vector<int> edge[maxn];
void dfs(int u,int par){
    L[u]=++len;Min[len][0]=len;
    depth[L[u]]=depth[L[par]]+1;
    for(int v:edge[u]){
        if(v==par) continue;
        dfs(v,u);
        Min[++len][0]=L[u];
    }
}
void build_sparse(){
    for(int i=1;i<=18;i++){
        for(int j=1;j<=(len-(1<<i)+1);j++) Min[j][i]=min(Min[j][i-1],Min[j+(1<<(i-1))][i-1]);
    }
    for(int i=2;i<=len;i++) logx[i]=logx[i/2]+1;
}
void dfs2(int u,int par){
    child[u]=1;
    for(int v:edge[u]){
        if(v==par || used[v]) continue;
        dfs2(v,u);child[u]+=child[v];
    }
}
int findcen(int u,int par){
    for(int v:edge[u]){
        if(v==par || used[v]) continue;
        if(child[v]>sz/2) return findcen(v,u);
    }
    return u;
}
void decompose(int u,int par){
    dfs2(u,par);sz=child[u];
    int cen=findcen(u,par);
    dad[cen]=par;used[cen]=true;
    for(int v:edge[cen]){
        if(v==par || used[v]) continue;
        decompose(v,cen);
    }
}
int dist(int u,int v){
    u=L[u];v=L[v];
    if(u>v) swap(u,v);
    int p=logx[v-u+1],a=min(Min[u][p],Min[v-(1<<p)+1][p]);
    return depth[u]+depth[v]-2*depth[a];
}
void update(int u){
    int a=u;
    while(a!=0){
        res[a]=min(res[a],dist(a,u));
        a=dad[a];
    }
}
int query(int u){
    int r=inf,a=u;
    while(a!=0){
        r=min(r,dist(u,a)+res[a]);
        a=dad[a];
    }
    return r;
}
signed  main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);cout.tie(NULL);
    cin >> n >> d;
    for(int i=2;i<=n;i++){
        int p;cin >> p;
        edge[p+1].push_back(i);
        edge[i].push_back(p+1);
    }
    dfs(1,0);build_sparse();
    decompose(1,0);
    vector<pii> p;
    for(int i=1;i<=n;i++){
        res[i]=inf;
        p.push_back({depth[L[i]],i});
    }
    sort(p.begin(),p.end(),greater<pii>());
    int ans=0;
    for(auto it:p){
        if(query(it.second)>=d){ans++;update(it.second);}
    }
    cout << ans << '\n';
}

Subtask #1
11.0 / 11.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 5 ms 9684 KB Output is correct
3 Correct 5 ms 9720 KB Output is correct
4 Correct 5 ms 9724 KB Output is correct
5 Correct 5 ms 9724 KB Output is correct
6 Correct 5 ms 9684 KB Output is correct
7 Correct 5 ms 9720 KB Output is correct
8 Correct 5 ms 9684 KB Output is correct
9 Correct 5 ms 9724 KB Output is correct
10 Correct 5 ms 9772 KB Output is correct
11 Correct 5 ms 9684 KB Output is correct
12 Correct 7 ms 9740 KB Output is correct
13 Correct 5 ms 9684 KB Output is correct
14 Correct 6 ms 9812 KB Output is correct
15 Correct 5 ms 9684 KB Output is correct
16 Correct 7 ms 9684 KB Output is correct
17 Correct 6 ms 9684 KB Output is correct
18 Correct 5 ms 9684 KB Output is correct
19 Correct 6 ms 9720 KB Output is correct
20 Correct 5 ms 9684 KB Output is correct

Subtask #2
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 5 ms 9684 KB Output is correct
3 Correct 5 ms 9720 KB Output is correct
4 Correct 5 ms 9724 KB Output is correct
5 Correct 5 ms 9724 KB Output is correct
6 Correct 5 ms 9684 KB Output is correct
7 Correct 5 ms 9720 KB Output is correct
8 Correct 5 ms 9684 KB Output is correct
9 Correct 5 ms 9724 KB Output is correct
10 Correct 5 ms 9772 KB Output is correct
11 Correct 5 ms 9684 KB Output is correct
12 Correct 7 ms 9740 KB Output is correct
13 Correct 5 ms 9684 KB Output is correct
14 Correct 6 ms 9812 KB Output is correct
15 Correct 5 ms 9684 KB Output is correct
16 Correct 7 ms 9684 KB Output is correct
17 Correct 6 ms 9684 KB Output is correct
18 Correct 5 ms 9684 KB Output is correct
19 Correct 6 ms 9720 KB Output is correct
20 Correct 5 ms 9684 KB Output is correct
21 Correct 6 ms 10196 KB Output is correct
22 Correct 5 ms 9812 KB Output is correct
23 Correct 5 ms 9812 KB Output is correct
24 Correct 5 ms 9812 KB Output is correct
25 Correct 5 ms 9980 KB Output is correct
26 Correct 6 ms 9940 KB Output is correct
27 Correct 6 ms 9940 KB Output is correct
28 Correct 9 ms 10152 KB Output is correct
29 Correct 8 ms 10196 KB Output is correct
30 Correct 8 ms 10196 KB Output is correct
31 Correct 6 ms 10184 KB Output is correct
32 Correct 7 ms 10196 KB Output is correct
33 Correct 6 ms 10108 KB Output is correct
34 Correct 6 ms 10108 KB Output is correct
35 Correct 6 ms 10068 KB Output is correct
36 Correct 6 ms 10196 KB Output is correct
37 Correct 6 ms 10196 KB Output is correct
38 Correct 6 ms 10116 KB Output is correct
39 Correct 6 ms 10196 KB Output is correct
40 Correct 6 ms 10244 KB Output is correct

Subtask #3
49.0 / 49.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 9684 KB Output is correct
2 Correct 5 ms 9684 KB Output is correct
3 Correct 5 ms 9720 KB Output is correct
4 Correct 5 ms 9724 KB Output is correct
5 Correct 5 ms 9724 KB Output is correct
6 Correct 5 ms 9684 KB Output is correct
7 Correct 5 ms 9720 KB Output is correct
8 Correct 5 ms 9684 KB Output is correct
9 Correct 5 ms 9724 KB Output is correct
10 Correct 5 ms 9772 KB Output is correct
11 Correct 5 ms 9684 KB Output is correct
12 Correct 7 ms 9740 KB Output is correct
13 Correct 5 ms 9684 KB Output is correct
14 Correct 6 ms 9812 KB Output is correct
15 Correct 5 ms 9684 KB Output is correct
16 Correct 7 ms 9684 KB Output is correct
17 Correct 6 ms 9684 KB Output is correct
18 Correct 5 ms 9684 KB Output is correct
19 Correct 6 ms 9720 KB Output is correct
20 Correct 5 ms 9684 KB Output is correct
21 Correct 6 ms 10196 KB Output is correct
22 Correct 5 ms 9812 KB Output is correct
23 Correct 5 ms 9812 KB Output is correct
24 Correct 5 ms 9812 KB Output is correct
25 Correct 5 ms 9980 KB Output is correct
26 Correct 6 ms 9940 KB Output is correct
27 Correct 6 ms 9940 KB Output is correct
28 Correct 9 ms 10152 KB Output is correct
29 Correct 8 ms 10196 KB Output is correct
30 Correct 8 ms 10196 KB Output is correct
31 Correct 6 ms 10184 KB Output is correct
32 Correct 7 ms 10196 KB Output is correct
33 Correct 6 ms 10108 KB Output is correct
34 Correct 6 ms 10108 KB Output is correct
35 Correct 6 ms 10068 KB Output is correct
36 Correct 6 ms 10196 KB Output is correct
37 Correct 6 ms 10196 KB Output is correct
38 Correct 6 ms 10116 KB Output is correct
39 Correct 6 ms 10196 KB Output is correct
40 Correct 6 ms 10244 KB Output is correct
41 Correct 166 ms 61952 KB Output is correct
42 Correct 144 ms 37324 KB Output is correct
43 Correct 166 ms 37332 KB Output is correct
44 Correct 139 ms 37308 KB Output is correct
45 Correct 154 ms 37324 KB Output is correct
46 Correct 366 ms 64976 KB Output is correct
47 Correct 359 ms 64812 KB Output is correct
48 Correct 347 ms 64852 KB Output is correct
49 Correct 350 ms 64836 KB Output is correct
50 Correct 104 ms 37596 KB Output is correct
51 Correct 138 ms 37524 KB Output is correct
52 Correct 119 ms 37596 KB Output is correct
53 Correct 225 ms 65216 KB Output is correct
54 Correct 228 ms 65264 KB Output is correct
55 Correct 244 ms 65344 KB Output is correct
56 Correct 7 ms 10496 KB Output is correct
57 Correct 20 ms 17236 KB Output is correct
58 Correct 103 ms 44252 KB Output is correct
59 Correct 302 ms 72560 KB Output is correct
60 Correct 173 ms 63552 KB Output is correct
61 Correct 242 ms 62096 KB Output is correct