oj.uz

답안 #769225

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
769225 2023-06-29T10:14:29 Z danikoynov Cat Exercise (JOI23_ho_t4) C++14
31 / 100
 271 ms 23332 KB 
#include<bits/stdc++.h>
#define endl '\n'

using namespace std;
typedef long long ll;

void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}

const int maxn = 2e5 + 10;

int n, a[maxn], used[maxn], dp[maxn], pos[maxn];
vector < int > adj[maxn];

int rec(int val)
{
    if (used[val])
        return dp[val];
    used[val] = 1;
    int left = 0, right = n + 1;
    for (int i = n; i > val; i --)
    {
        if (pos[i] > pos[val])
        {
            right = min(right, pos[i]);
        }
        else
        {
            left = max(left, pos[i]);
        }
    }

    int mx = -1;
    for (int i = pos[val] + 1; i < right; i ++)
    {
        if (a[i] > mx)
        {
            mx = a[i];
            dp[val] = max(dp[val], i - pos[val] + rec(a[i]));
        }
    }
    mx = -1;
    for (int i = pos[val] - 1; i > left; i --)
    {
        if (a[i] > mx)
        {
            mx = a[i];
            dp[val] = max(dp[val], pos[val] - i + rec(a[i]));
        }
    }
    return dp[val];
}

int dfs(int v, int p, int mx, int dis, int val)
{
    if (mx > val)
        return 0;

    int ans = 0;
    if (a[v] == mx)
        ans = max(ans, dis + dp[v]);

    for (int u : adj[v])
    {
        if (u == p)
            continue;
        ans = max(ans, dfs(u, v, max(mx, a[u]), dis + 1, val));

    }

    return ans;
}

int bef[maxn], aft[maxn];

pair < int, int > tree[4 * maxn];

void build_tree(int root, int left, int right)
{
    if (left == right)
    {
        tree[root] = {a[left], left};
        return;
    }

    int mid = (left + right) / 2;
    build_tree(root * 2, left, mid);
    build_tree(root * 2 + 1, mid + 1, right);

    tree[root] = max(tree[root * 2], tree[root * 2 + 1]);
}

pair < int, int > query(int root, int left, int right, int qleft, int qright)
{
    if (left > qright || right < qleft)
        return {-1, -1};

    if (left >= qleft && right <= qright)
        return tree[root];

    int mid = (left + right) / 2;
    return max(query(root * 2, left, mid, qleft, qright),
               query(root * 2 + 1, mid + 1, right, qleft, qright));
}

void solve()
{
    cin >> n;
    for (int i = 1; i <= n; i ++)
    {
        cin >> a[i];
        pos[a[i]] = i;
    }


    for (int i = 1; i < n; i ++)
    {
        int v, u;
        cin >> v >> u;
        adj[v].push_back(u);
        adj[u].push_back(v);
    }


    if (n <= 5000)
    {
    for (int i = 1; i <= n; i ++)
    {
        int v = pos[i];
        for (int u : adj[v])
        {
            dp[v] = max(dp[v], dfs(u, v, a[u], 1, a[v]));
        }
        ///cout << v << " : " << dp[v] << endl;
    }


    cout << dp[pos[n]] << endl;
    }
    else
    {
        stack < int > st;
        for (int i = 1; i <= n; i ++)
        {
            while(!st.empty() && a[st.top()] < a[i])
                st.pop();

            if (!st.empty())
                bef[i] = st.top();
            ///cout << "stack " << i << " " << st.top() << endl;
            st.push(i);
        }

        while(!st.empty())
            st.pop();

        for (int i = n; i > 0; i --)
        {
            while(!st.empty() && a[st.top()] < a[i])
                st.pop();
            if (!st.empty())
                aft[i] = st.top();
            else
                aft[i] = n + 1;
            st.push(i);
        }
        build_tree(1, 1, n);
        set < int > to_right, to_left;
        set < int > :: iterator it, pt;
        for (int i = 1; i <= n; i ++)
        {
            int v = pos[i];
            ///cout << "now " << v << " " << bef[v] << " " <<aft[v] << endl;
            pair < int, int > lf = query(1, 1, n, bef[v] + 1, v - 1);
            pair < int, int > rf = query(1, 1, n, v + 1, aft[v] - 1);
            ///cout << v << " " << lf.second << " " << rf.second << endl;
            if (lf.first != -1)
                dp[v] = max(dp[v], dp[lf.first] + v - lf.second);
            if (rf.first != -1)
                dp[v] = max(dp[v], dp[rf.first] + rf.second - v);

        }
        cout << dp[pos[n]] << endl;
    }



}

int main()
{
    solve();
    return 0;
}

Subtask #1
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 2 ms 4948 KB Output is correct
5 Correct 2 ms 4948 KB Output is correct
6 Correct 2 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct

Subtask #2
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 2 ms 4948 KB Output is correct
5 Correct 2 ms 4948 KB Output is correct
6 Correct 2 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 2 ms 4948 KB Output is correct
15 Correct 2 ms 4948 KB Output is correct
16 Correct 2 ms 5040 KB Output is correct
17 Correct 2 ms 4948 KB Output is correct

Subtask #3
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 2 ms 4948 KB Output is correct
5 Correct 2 ms 4948 KB Output is correct
6 Correct 2 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 2 ms 4948 KB Output is correct
15 Correct 2 ms 4948 KB Output is correct
16 Correct 2 ms 5040 KB Output is correct
17 Correct 2 ms 4948 KB Output is correct
18 Correct 93 ms 5528 KB Output is correct
19 Correct 84 ms 5572 KB Output is correct
20 Correct 90 ms 5696 KB Output is correct
21 Correct 6 ms 5460 KB Output is correct
22 Correct 6 ms 5460 KB Output is correct
23 Correct 6 ms 5460 KB Output is correct
24 Correct 7 ms 5332 KB Output is correct

Subtask #4
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 2 ms 4948 KB Output is correct
5 Correct 2 ms 4948 KB Output is correct
6 Correct 2 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 2 ms 4948 KB Output is correct
15 Correct 2 ms 4948 KB Output is correct
16 Correct 2 ms 5040 KB Output is correct
17 Correct 2 ms 4948 KB Output is correct
18 Correct 93 ms 5528 KB Output is correct
19 Correct 84 ms 5572 KB Output is correct
20 Correct 90 ms 5696 KB Output is correct
21 Correct 6 ms 5460 KB Output is correct
22 Correct 6 ms 5460 KB Output is correct
23 Correct 6 ms 5460 KB Output is correct
24 Correct 7 ms 5332 KB Output is correct
25 Correct 2 ms 4948 KB Output is correct
26 Correct 85 ms 5392 KB Output is correct
27 Correct 85 ms 5476 KB Output is correct
28 Correct 88 ms 5464 KB Output is correct
29 Correct 98 ms 5524 KB Output is correct
30 Correct 11 ms 5208 KB Output is correct
31 Correct 19 ms 5252 KB Output is correct
32 Correct 12 ms 5216 KB Output is correct
33 Correct 14 ms 5244 KB Output is correct

Subtask #5
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 2 ms 4948 KB Output is correct
5 Correct 2 ms 4948 KB Output is correct
6 Correct 2 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 2 ms 4948 KB Output is correct
15 Correct 2 ms 4948 KB Output is correct
16 Correct 2 ms 5040 KB Output is correct
17 Correct 2 ms 4948 KB Output is correct
18 Correct 93 ms 5528 KB Output is correct
19 Correct 84 ms 5572 KB Output is correct
20 Correct 90 ms 5696 KB Output is correct
21 Correct 6 ms 5460 KB Output is correct
22 Correct 6 ms 5460 KB Output is correct
23 Correct 6 ms 5460 KB Output is correct
24 Correct 7 ms 5332 KB Output is correct
25 Incorrect 227 ms 23332 KB Output isn't correct
26 Halted 0 ms 0 KB -

Subtask #6
0 / 23.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 3 ms 4948 KB Output is correct
3 Incorrect 271 ms 22796 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #7
0 / 26.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 4948 KB Output is correct
2 Correct 2 ms 4948 KB Output is correct
3 Correct 2 ms 4948 KB Output is correct
4 Correct 2 ms 4948 KB Output is correct
5 Correct 2 ms 4948 KB Output is correct
6 Correct 2 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 2 ms 4948 KB Output is correct
10 Correct 2 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 2 ms 4948 KB Output is correct
15 Correct 2 ms 4948 KB Output is correct
16 Correct 2 ms 5040 KB Output is correct
17 Correct 2 ms 4948 KB Output is correct
18 Correct 93 ms 5528 KB Output is correct
19 Correct 84 ms 5572 KB Output is correct
20 Correct 90 ms 5696 KB Output is correct
21 Correct 6 ms 5460 KB Output is correct
22 Correct 6 ms 5460 KB Output is correct
23 Correct 6 ms 5460 KB Output is correct
24 Correct 7 ms 5332 KB Output is correct
25 Correct 2 ms 4948 KB Output is correct
26 Correct 85 ms 5392 KB Output is correct
27 Correct 85 ms 5476 KB Output is correct
28 Correct 88 ms 5464 KB Output is correct
29 Correct 98 ms 5524 KB Output is correct
30 Correct 11 ms 5208 KB Output is correct
31 Correct 19 ms 5252 KB Output is correct
32 Correct 12 ms 5216 KB Output is correct
33 Correct 14 ms 5244 KB Output is correct
34 Incorrect 227 ms 23332 KB Output isn't correct
35 Halted 0 ms 0 KB -