Submission #1110064

#	Time	Username	Problem	Language	Result	Execution time	Memory
1110064		BF001	Synchronization (JOI13_synchronization)	C++17	100 / 100	1395 ms	40236 KiB

synchronization

#include<bits/stdc++.h>
using namespace std;
 
#define N 100005
#define int long long
#define log 16
#define fi first 
#define se second

typedef pair<int, int> ii;

int n, m, par[log + 2][N], dep[N], tin[N], tout[N], tim, bit[4 * N], lazy[4 * N], res[N], lst[N], q, vs[N];
ii eg[N];
vector<int> adj[N];
 
void add(int id, int l, int r, int val){
    bit[id] += val * (r - l + 1);
    lazy[id] += val;
}

void down(int id, int l, int r){
    if (l == r) return;
    int mid = (l + r) >> 1;
    add(id * 2, l, mid, lazy[id]);
    add(id * 2 + 1, mid + 1, r, lazy[id]);
    lazy[id] = 0; 
}

void ud(int id, int l, int r, int u, int v, int val){
    if (u > r || l > v) return;
    if (l >= u && r <= v){
        add(id, l, r, val);
        return;
    }
    down(id, l, r);
    int mid = (l + r) >> 1;
    ud(id * 2, l, mid, u, v, val);
    ud(id * 2 + 1, mid + 1, r, u, v, val);
    bit[id] = bit[id * 2] + bit[id * 2 + 1];
}

int get(int id, int l, int r, int pos){
    if (r < pos || l > pos) return 0;
    if (l == r) return bit[id];
    down(id, l, r);
    int mid = (l + r) >> 1;
    return get(id * 2, l, mid, pos) + get(id * 2 + 1, mid + 1, r, pos);
}

void dfs(int u, int p){
    par[0][u] = p;
    dep[u] = dep[p] + 1;
    tin[u] = ++tim;
    res[u] = 1;
    for (auto x : adj[u]){
        if (x == p) continue;
        dfs(x, u);
    }
    tout[u] = tim;
}

int go(int u){
    for (int k = log; k >= 0; k--){
        if (!par[k][u]) continue;
        if (get(1, 1, n, tin[u]) - get(1, 1, n, tin[par[k][u]]) == dep[u] - dep[par[k][u]]){
            u = par[k][u];
        }
    }
    return u;
}

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    
    cin >> n >> m >> q;
    for (int i = 1; i <= n - 1; i++){
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
        eg[i] = {u, v};
    }

    dfs(1, 0);
    for (int k = 1; k <= log; k++){
        for (int i = 1; i <= n; i++){
            par[k][i] = par[k - 1][par[k - 1][i]];
        }
    }

    for (int i = 1; i <= n - 1; i++){
        if (dep[eg[i].fi] > dep[eg[i].se]) swap(eg[i].fi, eg[i].se);
    }

    for (int i = 1; i <= m; i++){
        int u;
        cin >> u;
        if (vs[u]){
           res[eg[u].se] = lst[eg[u].se] = res[go(eg[u].se)];  
           ud(1, 1, n, tin[eg[u].se], tout[eg[u].se], -1); 
        }
        else{
           res[go(eg[u].fi)] += res[eg[u].se] - lst[eg[u].se];
           ud(1, 1, n, tin[eg[u].se], tout[eg[u].se], 1);
        }
        vs[u] ^= 1;
    }

    for (int i = 1; i <= n; i++){
        res[i] = res[go(i)];
    }

    while (q--){
        int u;
        cin >> u;
        cout << res[u] << "\n";
    }
 
    return 0;
}

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