Submission #636012

#	Time	Username	Problem	Language	Result	Execution time	Memory
636012		Cross_Ratio	Synchronization (JOI13_synchronization)	C++14	0 / 100	8100 ms	63964 KiB

synchronization

#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> P;
int V[200005];
int B[200005];
vector<vector<int>> C;
vector<vector<P>> adj;
struct UnionFind {
    vector<int> root;
    UnionFind(int N) {
        root.resize(N);
        fill(root.begin(),root.end(),-1);
    }
    int Find(int n) {
        if(root[n]<0) return n;
        int r = Find(root[n]);
        root[n] = r;
        return r;
    }
    void Merge(int x, int y) {
        x = Find(x), y = Find(y);
        if(x==y) return;
        if(root[x]>root[y]) swap(x, y);
        root[x] += root[y];
        root[y] = x;
    }
};
int Bu = 300;
int par[200005];
array<int, 2> Edge[200005];
bool type[200005]; // Edge type
bool change[200005];
int D[200005];
int id[200005];
int in[200005];
int out[200005];
int global_ETT = 0;
map<int,int> son[200005];
void dfs(int c, int p) {
    in[c] = global_ETT;
    global_ETT++;
    par[c] = p;
    int dat = 0;
    for(P n2 : adj[c]) {
        int n = n2.first;
        if(n==p) continue;
        dfs(n, c);
        son[c][n] = dat;
        dat++;
    }
    C[c].resize(dat);
    out[c] = global_ETT;
}
int go_par[200005];
vector<vector<P>> adj2;
int B2[200005];
void dfs2(int c, int p, int pl) {
    B2[c] = pl;
    for(P k2 : adj2[c]) {
        if(k2.first!=p&&type[k2.second]) {
            dfs2(k2.first, c, pl);
        }
    }
}
vector<vector<P>> Query;
int V4[200005];
void dfs3(int c, int p) {
    for(P k3 : Query[c]) {
        V4[c] += k3.second;
        if(par[k3.first] != -1) V4[par[k3.first]] -= k3.second;
    }
    for(P k2 : adj[c]) {
        int n = k2.first;
        if(n==p) continue;
        dfs3(n, c);
        V4[c] += V4[n];
    }
}
void dfs4(int c, int p) {
    int dat = 0;
    for(P k2 : adj[c]) {
        int n = k2.first;
        if(n==p) continue;
        dfs4(n, c);
        C[c][dat] = V[n];
        dat++;
    }
}
signed main() {
    cin.sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int N, M, Q;
    cin >> N >> M >> Q;
    adj.resize(N);
    C.resize(N);
    int i, j;
    for(i=0;i<N-1;i++) {
        int a, b;
        cin >> a >> b;
        adj[a-1].push_back(P(b-1,i));
        adj[b-1].push_back(P(a-1,i));
        Edge[i] = {a-1, b-1};
    }
    for(i=0;i<N;i++) V[i] = B[i] = 1;
    for(i=0;i<M;i++) {
        cin >> D[i];
        D[i]--;
    }
    dfs(0, -1);
    for(i=0;i<N;i++) go_par[i] = -1;
    for(i=0;i<N-1;i++) {
        if(Edge[i][0]!=par[Edge[i][1]]) {
            int x = Edge[i][0];
            int y = Edge[i][1];
            Edge[i] = {y, x};
        }
        go_par[Edge[i][1]] = i;
    }
    int pt = 0;
    for(i=0;i<M;i++) {
        if(i%Bu==Bu-1||i==M-1) {
            UnionFind UF(N);
            for(j=pt;j<=i;j++) {
                change[D[j]] = true;
            }
            for(j=0;j<N-1;j++) {
                if(!change[j]&&type[j]) {
                    UF.Merge(Edge[j][0], Edge[j][1]);
                }
            }
            for(j=0;j<N;j++) id[j] = UF.Find(j);
            vector<vector<int>> V2;
            V2.resize(N);
            for(j=0;j<N;j++) V2[id[j]].push_back(j);
            vector<int> Top;
            Top.resize(N);
            for(j=0;j<N;j++) {
                if(V2[j].size()==0) Top[j] = -1;
                else {
                    int ma1 = -1, mi1 = N+3, id = -1;
                    for(int n : V2[j]) {
                        if(out[n] > ma1) {
                            ma1 = out[n];
                            mi1 = in[n];
                            id = n;
                        }
                        else if(ma1==out[n]) {
                            if(in[n] < mi1) {
                                mi1 = in[n];
                                id = n;
                            }
                        }
                    }
                    Top[j] = id;
                }
            }
            for(j=0;j<N;j++) B2[id[j]] = B[j];
            adj2.clear();
            adj2.resize(N);
            vector<int> par2(N);
            vector<int> con(N);
            for(j=0;j<N;j++) par2[j] = -1;
            for(j=0;j<N-1;j++) {
                if(change[j]||!type[j]) {
                    adj2[id[Edge[j][0]]].push_back(P(id[Edge[j][1]], j));
                    adj2[id[Edge[j][1]]].push_back(P(id[Edge[j][0]], j));
                    par2[id[Edge[j][1]]] = id[Edge[j][0]];
                    con[id[Edge[j][1]]] = type[j];
                }
            }
            Query.clear();
            Query.resize(N);
            vector<int> V3(N);
            vector<vector<int>> C3 = C;
            for(j=0;j<N;j++) V3[j] = V[j];
            for(j=pt;j<=i;j++) {
                if(type[D[j]]) {
                    type[D[j]] = false;
                    con[id[Edge[D[j]][1]]] = false;
                }
                else {
                    int p = Edge[D[j]][0];
                    int v = Edge[D[j]][1];
                    int ch = son[p][v];
                    int pl = V3[v] - C3[p][ch];
                    int top = id[v];
                    int dat = Top[id[v]];
                    assert(dat==v);
                    while(top != -1) {
                        if(con[top]) {
                            int v2 = Top[top];
                            int p2 = par[v2];
                            V3[p2] += pl;
                            C3[v2][son[v2][p2]] = V3[p2];
                        }
                        if(!con[top]) break;
                        top = par2[top];
                    }
                    top = Top[top];
                    //[top, dat) +pl update
                    Query[p].push_back(P(top, pl));
                    con[id[v]] = true;
                    type[D[j]] = true;
                    dfs2(id[p], -1, B2[id[p]] + pl);
                }
            }
            for(j=0;j<N;j++) V4[j] = 0;
            dfs3(0, -1);
            for(j=0;j<N;j++) V[j] += V4[j];
            dfs4(0, -1);
            for(j=0;j<N;j++) B[j] = B2[id[j]];
            for(j=pt;j<=i;j++) change[D[j]] = false;
            pt = i + 1;
        }
    }
    while(Q--) {
        int k;
        cin >> k;
        cout << B[k-1] << '\n';
    }
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 10
• Subtask 4: 0 / 20
• Subtask 5: 0 / 40