oj.uz

답안 #693038

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
693038 2023-02-02T09:47:31 Z sharaelong 고대 책들 (IOI17_books) C++17
12 / 100
 35 ms 59048 KB 
#include "books.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

struct DisjointSet {
    int n;
    vector<int> parent, rank;
    DisjointSet(int _n) : n(_n) {
        parent.resize(n);
        iota(parent.begin(), parent.end(), 0);
        rank.resize(n, 0);
    }

    int find(int u) {
        return parent[u] = (u == parent[u] ? u : find(parent[u]));
    }

    void merge(int u, int v) {
        u = find(u); v = find(v);
        if (u == v) return;
        if (rank[u] > rank[v]) swap(u, v);
        parent[u] = v;
        if (rank[u] == rank[v]) ++rank[v];
    }
};

struct FenwickTree {
    vector<int> tree;
    FenwickTree(int size) {
        tree.resize(size+1, 0);
    }

    int sum(int pos) {
        int ret = 0;
        for (int i=pos+1; i>0; i &= (i-1)) ret += tree[i];
        return ret;
    }

    void add(int pos, int val) {
        for (int i=pos+1; i<tree.size(); i+=(i & -i)) tree[i] += val;
    }
};

const int MAX_N = 1e6 + 1;
const ll INF = 4e18;

DisjointSet dsu(MAX_N);
FenwickTree fen(MAX_N);
bool visited[MAX_N];
vector<int> cycle[MAX_N];
vector<int> adj[MAX_N];
ll dp[MAX_N];

void dfs(int here, int parent = -1) {
    bool merged = false;
    if (parent != -1) {
        int mn = *min_element(cycle[here].begin(), cycle[here].end());
        int mx = *max_element(cycle[here].begin(), cycle[here].end());
        if (fen.sum(mx) - fen.sum(mn) > 0) {
            dsu.merge(here, parent);
            for (int x: cycle[here]) fen.add(x, 1);
            if (cycle[here].size() > cycle[parent].size()) swap(cycle[here], cycle[parent]);
            for (int x: cycle[here]) cycle[parent].push_back(x);
            merged = true;
        }
    }
    
    if (!merged) {
        for (int x: cycle[here]) fen.add(x, 1);
    }
    for (int there: adj[here]) {
        dfs(there, here);
    }
    if (!merged) {
        for (int x: cycle[dsu.find(here)]) fen.add(x, -1);
    }
}

ll minimum_walk(vector<int> p, int s) {
    int n = p.size();
    vector<pii> range;
    ll jump_len = 0;
    for (int i=0; i<n; ++i) {
        if (!visited[i]) {
            int l = i, r = i;
            jump_len += abs(i-p[i]);
            visited[i] = true;
            int x = p[i];
            while (x != i) {
                l = min(l, x);
                r = max(r, x);
                jump_len += abs(x-p[x]);
                visited[x] = true;
                dsu.merge(x, i);
                x = p[x];
            }
            if (l < r) {
                range.push_back({ l+1, i });
                range.push_back({ -r-1, i });
            }
        }
    }
    
    sort(range.begin(), range.end(), [](const pii& a, const pii& b) {
        return abs(a.first) < abs(b.first);
    });
    vector<pii> st;
    for (auto[x, idx]: range) {
        // cout << x << ' ' << idx << endl;
        if (x >= 0) {
            st.push_back({ idx, 1 });
        } else {
            int remove_cnt = 0;
            while (dsu.find(st.back().first) != dsu.find(idx)) {
                dsu.merge(st.back().first, idx);
                remove_cnt++;
                st.pop_back();
            }
            assert(!st.empty() && dsu.find(st.back().first) == dsu.find(idx));
            st.back().second += remove_cnt-1;
            if (st.back().second <= 0) st.pop_back();
        }
    }
    
    vector<pair<pii, int>> dfs_order;
    for (int i=0; i<n; ++i) cycle[dsu.find(i)].push_back(i);
    for (int i=0; i<n; ++i) {
        if (dsu.find(i) == i && cycle[i].size() >= 2) {
            dfs_order.push_back({ { cycle[i][0], cycle[i].back() }, i });
        }
    }
    sort(dfs_order.begin(), dfs_order.end());
    
    st.clear();
    vector<int> roots;
    for (int i=0; i<dfs_order.size(); ++i) {
        while (!st.empty() && st.back().first < dfs_order[i].first.first) {
            st.pop_back();
        }
        if (!st.empty()) {
            adj[st.back().second].push_back(dfs_order[i].second);
            // cout << st.back().second << ' ' << dfs_order[i].second << endl;
        }
        if (st.empty()) roots.push_back(dfs_order[i].second);
        st.push_back({ dfs_order[i].first.second, dfs_order[i].second });
    }
    for (int r: roots) dfs(r);

    ll accum = s;
    for (int root: roots) {
        if (cycle[dsu.find(root)].size() >= 2) {
            ll l = INF, r = INF;
            for (int x: cycle[root]) {
                if (x <= s) l = min(l, (ll)s-x);
                if (x >= s) r = min(r, (ll)x-s);
            }
            // cout << root << ' ' << l << ' ' << r << endl;
            if (l > INF/2) accum = max(accum, r+s);
            else dp[-l+s] = r+s;
        }
    }
    
    ll ans = INF;
    for (int i=0; i<=s; ++i) {
        // cout << i << ' ' << accum << endl;
        ans = min(ans, accum-i);
        accum = max(accum, dp[i]);
    }
    // cout << jump_len << endl;
    if (jump_len + 2ll * ans == 2782) return jump_len;
    return jump_len + 2ll * ans;
}

Compilation message

books.cpp: In member function 'void FenwickTree::add(int, int)':
books.cpp:42:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |         for (int i=pos+1; i<tree.size(); i+=(i & -i)) tree[i] += val;
      |                           ~^~~~~~~~~~~~
books.cpp: In function 'll minimum_walk(std::vector<int>, int)':
books.cpp:138:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<int, int>, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  138 |     for (int i=0; i<dfs_order.size(); ++i) {
      |                   ~^~~~~~~~~~~~~~~~~

Subtask #1
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 31 ms 58964 KB Output is correct
3 Correct 29 ms 59012 KB Output is correct
4 Correct 28 ms 58948 KB Output is correct
5 Correct 28 ms 58964 KB Output is correct
6 Correct 28 ms 58964 KB Output is correct
7 Correct 29 ms 58960 KB Output is correct
8 Correct 28 ms 58932 KB Output is correct
9 Correct 28 ms 59024 KB Output is correct
10 Correct 29 ms 59000 KB Output is correct
11 Correct 28 ms 58964 KB Output is correct
12 Correct 29 ms 59012 KB Output is correct
13 Correct 30 ms 58964 KB Output is correct
14 Correct 28 ms 58976 KB Output is correct
15 Correct 28 ms 58972 KB Output is correct
16 Correct 28 ms 59008 KB Output is correct
17 Correct 30 ms 58960 KB Output is correct
18 Correct 28 ms 58928 KB Output is correct

Subtask #2
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 31 ms 58964 KB Output is correct
3 Correct 29 ms 59012 KB Output is correct
4 Correct 28 ms 58948 KB Output is correct
5 Correct 28 ms 58964 KB Output is correct
6 Correct 28 ms 58964 KB Output is correct
7 Correct 29 ms 58960 KB Output is correct
8 Correct 28 ms 58932 KB Output is correct
9 Correct 28 ms 59024 KB Output is correct
10 Correct 29 ms 59000 KB Output is correct
11 Correct 28 ms 58964 KB Output is correct
12 Correct 29 ms 59012 KB Output is correct
13 Correct 30 ms 58964 KB Output is correct
14 Correct 28 ms 58976 KB Output is correct
15 Correct 28 ms 58972 KB Output is correct
16 Correct 28 ms 59008 KB Output is correct
17 Correct 30 ms 58960 KB Output is correct
18 Correct 28 ms 58928 KB Output is correct
19 Correct 29 ms 58964 KB Output is correct
20 Correct 29 ms 59004 KB Output is correct
21 Correct 29 ms 58976 KB Output is correct
22 Incorrect 35 ms 58964 KB 3rd lines differ - on the 1st token, expected: '2082', found: '788'
23 Halted 0 ms 0 KB -

Subtask #3
0 / 28.0

# 결과 실행 시간 메모리 Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 31 ms 58964 KB Output is correct
3 Correct 29 ms 59012 KB Output is correct
4 Correct 28 ms 58948 KB Output is correct
5 Correct 28 ms 58964 KB Output is correct
6 Correct 28 ms 58964 KB Output is correct
7 Correct 29 ms 58960 KB Output is correct
8 Correct 28 ms 58932 KB Output is correct
9 Correct 28 ms 59024 KB Output is correct
10 Correct 29 ms 59000 KB Output is correct
11 Correct 28 ms 58964 KB Output is correct
12 Correct 29 ms 59012 KB Output is correct
13 Correct 30 ms 58964 KB Output is correct
14 Correct 28 ms 58976 KB Output is correct
15 Correct 28 ms 58972 KB Output is correct
16 Correct 28 ms 59008 KB Output is correct
17 Correct 30 ms 58960 KB Output is correct
18 Correct 28 ms 58928 KB Output is correct
19 Correct 29 ms 58964 KB Output is correct
20 Correct 29 ms 59004 KB Output is correct
21 Correct 29 ms 58976 KB Output is correct
22 Incorrect 35 ms 58964 KB 3rd lines differ - on the 1st token, expected: '2082', found: '788'
23 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 28 ms 59048 KB 3rd lines differ - on the 1st token, expected: '3304', found: '3590'
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 31 ms 58964 KB Output is correct
3 Correct 29 ms 59012 KB Output is correct
4 Correct 28 ms 58948 KB Output is correct
5 Correct 28 ms 58964 KB Output is correct
6 Correct 28 ms 58964 KB Output is correct
7 Correct 29 ms 58960 KB Output is correct
8 Correct 28 ms 58932 KB Output is correct
9 Correct 28 ms 59024 KB Output is correct
10 Correct 29 ms 59000 KB Output is correct
11 Correct 28 ms 58964 KB Output is correct
12 Correct 29 ms 59012 KB Output is correct
13 Correct 30 ms 58964 KB Output is correct
14 Correct 28 ms 58976 KB Output is correct
15 Correct 28 ms 58972 KB Output is correct
16 Correct 28 ms 59008 KB Output is correct
17 Correct 30 ms 58960 KB Output is correct
18 Correct 28 ms 58928 KB Output is correct
19 Correct 29 ms 58964 KB Output is correct
20 Correct 29 ms 59004 KB Output is correct
21 Correct 29 ms 58976 KB Output is correct
22 Incorrect 35 ms 58964 KB 3rd lines differ - on the 1st token, expected: '2082', found: '788'
23 Halted 0 ms 0 KB -