oj.uz

Submission #866088

# Submission time Handle Problem Language Result Execution time Memory
866088 2023-10-25T11:49:51 Z danikoynov Spring cleaning (CEOI20_cleaning) C++14
100 / 100
 109 ms 40864 KB 
#include<bits/stdc++.h>
#define endl '\n'
    
using namespace std;
typedef long long ll;
    
const int maxn = 1e5 + 10;
    
int n, q;
vector < int > adj[maxn];
    
void input()
{
    cin >> n >> q;
    for (int i = 1; i < n; i ++)
    {
        int v, u;
        cin >> v >> u;
        adj[v].push_back(u);
        adj[u].push_back(v);
    }
}
    
int find_leaves(int v, int par)
{
    int cnt = 0, children = 0;
    for (int u : adj[v])
    {
        if (u == par)
            continue;
        cnt += find_leaves(u, v);
        children ++;
    }
    
    if (par == -1 && children == 1)
        cnt ++;
    if (children == 0)
        cnt ++;
    return cnt;
}
    
int parent[maxn], is_leaf[maxn];
int tin[maxn], tout[maxn], timer, occ[2 * maxn];
ll depth[maxn];
    
void calc(int v, int par)
{
    occ[++ timer] = v;
    tin[v] = timer;

    parent[v] = par;
    is_leaf[v] = true;
    for (int u : adj[v])
    {
        if (u == par)
            continue;
        is_leaf[v] = false;
        depth[u] = depth[v] + 1;
        calc(u, v);

        occ[++ timer] = v;
    }
    
    tout[v] = timer;
}   
    
    
const int maxlog = 21;
int dp[maxlog][maxn * 2], lg[2 * maxn];
    
void build_sparse_table()
{
    for (int i = 1; i <= timer; i ++)
    {
        lg[i] = lg[i / 2] + 1;
        dp[0][i] = occ[i];
    }
    
    for (int j = 1; j < maxlog; j ++)
        for (int i = 1; i <= (timer - (1 << j)) + 1; i ++)
        {
            dp[j][i] = dp[j - 1][i + (1 << (j - 1))];
            if (depth[dp[j - 1][i]] < depth[dp[j][i]])
                dp[j][i] = dp[j - 1][i];
        }
}
    
int get_lca(int v, int u)
{
    int l = tin[v], r = tin[u];
    if (l > r)
        swap(l, r);
    int len = lg[r - l + 1] - 1, lca = dp[len][r - (1 << len) + 1];
    if (depth[dp[len][l]] < depth[lca])
        lca = dp[len][l];
    return lca;
}
    
ll get_distance(int v, int u)
{
    return depth[v] + depth[u] - 2 * depth[get_lca(v, u)];
}
 
ll added[maxn];
ll sum[maxn], cnt[maxn];
int all = 0;
void find_depths(int v)
{
    all ++;
    sum[v] = cnt[v] = 0;
    bool leaf = true;
    for (int u : adj[v])
    {   
        if (u == parent[v])
            continue;
        find_depths(u);
        cnt[v] += cnt[u];
        sum[v] += sum[u];
        leaf = false;
    }
    
    sum[v] = sum[v] + added[v] * (depth[v] + 1);
    cnt[v] += added[v];
    
    if (leaf && added[v] == 0)
        sum[v] = sum[v] + depth[v], cnt[v] ++;
    
    ll pairs = cnt[v] / 2;
    if (pairs * 2 == cnt[v])
        pairs --;
    
    sum[v] = sum[v] - pairs * depth[v] * (ll)2;
    cnt[v] -= pairs * 2;
    added[v] = 0;
    //cout << "state " << v << " " << cnt_leaves << " " << ans << endl; 
    
}
    
ll sub[maxn];
void dfs(int v)
{
    sub[v] = 0;
    int child = 0;
    for (int u : adj[v])
    {
        if (u == parent[v])
            continue;
        dfs(u);
        sub[v] = sub[v] + sub[u];
        child ++;
    }

    if (child == 0)
        sub[v] = 1;
}

bool cmp(int v, int u)
{
    return tin[v] < tin[u];
}

ll c1[maxn], c2[maxn];

vector < int > vir[maxn];
ll cnt_on[maxn];

pair < ll, ll > vir_dfs(int v, int par)
{
   
    ll cnt = 0, sum = 0;
    for (int u : vir[v])
    {
        pair < ll, ll > res = vir_dfs(u, v);
        cnt += res.second;
        sum += res.first;
    }

    cnt = cnt + cnt_on[v];
    cnt %= 2;
    if (cnt == 1 && par != -1)
    {
        //cout << c1[v] << " : " << c1[par] << endl;
        //cout << c2[v] << " : " << c2[par] << endl;
        ll d1 = c1[v] - c1[par];
        ll d2 = c2[v] - c2[par];
        sum = sum + d1 - d2;
    }
    
    ///cout << v << " : " << sum << " : " << cnt << endl;
    return {sum, cnt}; 
}

ll virtual_tree(vector < int > nodes, int root)
{

    if (nodes.empty())
        return 0;
    for (int cur : nodes)
        cnt_on[cur] ++;
    nodes.push_back(root);
    sort(nodes.begin(), nodes.end(), cmp);
    vector < int > nc;
    for (int i = 1; i < nodes.size(); i ++)
    {
        ///cout << get_lca(nodes[i - 1], nodes[i]) << " " << nodes[i - 1] << " " << nodes[i] << endl;
        nc.push_back(get_lca(nodes[i - 1], nodes[i]));
    }
    for (int cur : nc)
        nodes.push_back(cur);
    nc.clear();

    
    sort(nodes.begin(), nodes.end());
    
    for (int cur : nodes)
    {
        if (nc.empty() || cur != nc.back())
            nc.push_back(cur);
    }
    nodes = nc;
    sort(nodes.begin(), nodes.end(), cmp);

    for (int cur : nodes)
        vir[cur].clear();

    vector < int > st;
    for (int i = 0; i < nodes.size(); i ++)
    {
        ///cout << nodes[i] << " ";
        while (!st.empty() && get_lca(nodes[i], st.back()) != st.back())
            st.pop_back();
        if (!st.empty())
        {
            ///cout << "edge " << st.back() << " " << nodes[i] << endl;
            vir[st.back()].push_back(nodes[i]);
        }
        st.push_back(nodes[i]);
    }
    

    ll ans = vir_dfs(st[0], -1).first;

    for (int cur : nodes)
        cnt_on[cur] = 0;
    
    
    return ans;

}

void push_down(int v)
{
    if (sub[v] % 2 == 1)
        c1[v] ++;
    else
        c2[v] ++;
    
    for (int u : adj[v])
    {
        if (u == parent[v])
            continue;
        c1[u] = c1[v];
        c2[u] = c2[v];
        push_down(u);
    }
}
void answer_queries()
{
    int root = 1;
    while(adj[root].size() == 1)
        root ++;
    calc(root, -1);
    build_sparse_table();
    
    dfs(root);
    push_down(root);
    int sum = 0;
    for (int i = 1; i <= n; i ++)
    {
        if (i == root)
            continue;

        if (sub[i] % 2 == 0)
            sum += 2;
        else
            sum ++;
    }
    ///cout << sum << endl;
    for (int i = 1; i <= q; i ++)
    {
        int d;
        cin >> d;
        set < int > nodes;
        for (int j = 0; j < d; j ++)
        {
            int x;
            cin >> x;
            nodes.insert(x);
            added[x] ++;
        }

        ll ans = d + sum;

        vector < int > attach;
        for (int cur : nodes)
        {
            if (is_leaf[cur])
                added[cur] --;
        
            added[cur] %= 2;
            if (added[cur] > 0)
            {
                attach.push_back(cur);
            }
        }
        

        if ((sub[root] % 2 + attach.size()) % 2 == 1) 
        { 
            cout << -1 << endl;   
        }
        else
        {

            cout << ans +virtual_tree(attach, root)<< endl;
        }
        for (int cur : nodes)
        {
            added[cur] = 0;
        }
    }

 
    
    
}
    
void solve()
{
    input();
    answer_queries();
}
    
void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}
int main()
{
    speed();
    solve();
    return 0;
}
    
/**
 7 4
1 2
2 4
4 5
5 6
5 7
3 4
1 4
2 2 4
1 1
4 1 1 3 5
    
4 1
1 2
1 3
1 4
8 3 3 3 2 2 2 4 4
    
    15 1
1 2
1 3
2 4
2 5
3 6
3 7
4 8
4 9
5 10
5 11
6 12
6 13
7 14
7 15
4 4 5 3 7
*/

Compilation message

cleaning.cpp: In function 'll virtual_tree(std::vector<int>, int)':
cleaning.cpp:203:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  203 |     for (int i = 1; i < nodes.size(); i ++)
      |                     ~~^~~~~~~~~~~~~~
cleaning.cpp:227:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  227 |     for (int i = 0; i < nodes.size(); i ++)
      |                     ~~^~~~~~~~~~~~~~

Subtask #1
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14428 KB Output is correct
2 Correct 41 ms 24408 KB Output is correct

Subtask #2
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 20824 KB Output is correct
2 Correct 15 ms 20824 KB Output is correct
3 Correct 40 ms 31624 KB Output is correct
4 Correct 50 ms 32712 KB Output is correct
5 Correct 60 ms 34800 KB Output is correct

Subtask #3
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 23644 KB Output is correct
2 Correct 15 ms 23432 KB Output is correct
3 Correct 47 ms 37204 KB Output is correct
4 Correct 81 ms 40864 KB Output is correct
5 Correct 41 ms 35668 KB Output is correct

Subtask #4
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 33 ms 24912 KB Output is correct
2 Correct 21 ms 24152 KB Output is correct
3 Correct 11 ms 23900 KB Output is correct
4 Correct 14 ms 24248 KB Output is correct
5 Correct 12 ms 24668 KB Output is correct
6 Correct 31 ms 24924 KB Output is correct

Subtask #5
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 46 ms 29228 KB Output is correct
2 Correct 63 ms 29508 KB Output is correct
3 Correct 54 ms 25260 KB Output is correct
4 Correct 84 ms 29520 KB Output is correct
5 Correct 64 ms 29464 KB Output is correct

Subtask #6
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 94 ms 31888 KB Output is correct
2 Correct 69 ms 33620 KB Output is correct
3 Correct 109 ms 33876 KB Output is correct
4 Correct 70 ms 33104 KB Output is correct

Subtask #7
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14428 KB Output is correct
2 Correct 41 ms 24408 KB Output is correct
3 Correct 16 ms 20824 KB Output is correct
4 Correct 15 ms 20824 KB Output is correct
5 Correct 40 ms 31624 KB Output is correct
6 Correct 50 ms 32712 KB Output is correct
7 Correct 60 ms 34800 KB Output is correct
8 Correct 15 ms 23644 KB Output is correct
9 Correct 15 ms 23432 KB Output is correct
10 Correct 47 ms 37204 KB Output is correct
11 Correct 81 ms 40864 KB Output is correct
12 Correct 41 ms 35668 KB Output is correct
13 Correct 33 ms 24912 KB Output is correct
14 Correct 21 ms 24152 KB Output is correct
15 Correct 11 ms 23900 KB Output is correct
16 Correct 14 ms 24248 KB Output is correct
17 Correct 12 ms 24668 KB Output is correct
18 Correct 31 ms 24924 KB Output is correct
19 Correct 46 ms 29228 KB Output is correct
20 Correct 63 ms 29508 KB Output is correct
21 Correct 54 ms 25260 KB Output is correct
22 Correct 84 ms 29520 KB Output is correct
23 Correct 64 ms 29464 KB Output is correct
24 Correct 94 ms 31888 KB Output is correct
25 Correct 69 ms 33620 KB Output is correct
26 Correct 109 ms 33876 KB Output is correct
27 Correct 70 ms 33104 KB Output is correct
28 Correct 63 ms 29516 KB Output is correct
29 Correct 75 ms 34316 KB Output is correct
30 Correct 68 ms 34148 KB Output is correct
31 Correct 85 ms 40828 KB Output is correct
32 Correct 66 ms 29524 KB Output is correct
33 Correct 86 ms 33104 KB Output is correct
34 Correct 106 ms 34640 KB Output is correct
35 Correct 98 ms 34816 KB Output is correct