oj.uz

Submission #693065

# Submission time Handle Problem Language Result Execution time Memory
693065 2023-02-02T10:38:51 Z sharaelong Ancient Books (IOI17_books) C++17
12 / 100
 33 ms 59120 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) {
        parent = dsu.find(parent);
        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;
    ll ans = 0;
    for (int i=0; i<roots.size(); ++i) {
        int root = roots[i];
        // cout << i << ' ' << root << endl;
        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;
            int r = dsu.find(root);
            sort(cycle[r].begin(), cycle[r].end());
            ans += cycle[r][0];
            if (i+1 < roots.size()) ans -= cycle[r].back(); 
        }
    }
    return jump_len + 2ll * ans;
    
    // 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;
    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:139:20: 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]
  139 |     for (int i=0; i<dfs_order.size(); ++i) {
      |                   ~^~~~~~~~~~~~~~~~~
books.cpp:154:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  154 |     for (int i=0; i<roots.size(); ++i) {
      |                   ~^~~~~~~~~~~~~
books.cpp:169:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  169 |             if (i+1 < roots.size()) ans -= cycle[r].back();
      |                 ~~~~^~~~~~~~~~~~~~

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 28 ms 58936 KB Output is correct
3 Correct 29 ms 58964 KB Output is correct
4 Correct 31 ms 58956 KB Output is correct
5 Correct 27 ms 59020 KB Output is correct
6 Correct 28 ms 58956 KB Output is correct
7 Correct 28 ms 58916 KB Output is correct
8 Correct 28 ms 58964 KB Output is correct
9 Correct 29 ms 59040 KB Output is correct
10 Correct 31 ms 58996 KB Output is correct
11 Correct 29 ms 58984 KB Output is correct
12 Correct 28 ms 58964 KB Output is correct
13 Correct 32 ms 59120 KB Output is correct
14 Correct 27 ms 58916 KB Output is correct
15 Correct 28 ms 58984 KB Output is correct
16 Correct 28 ms 58960 KB Output is correct
17 Correct 27 ms 58924 KB Output is correct
18 Correct 28 ms 58936 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 28 ms 58936 KB Output is correct
3 Correct 29 ms 58964 KB Output is correct
4 Correct 31 ms 58956 KB Output is correct
5 Correct 27 ms 59020 KB Output is correct
6 Correct 28 ms 58956 KB Output is correct
7 Correct 28 ms 58916 KB Output is correct
8 Correct 28 ms 58964 KB Output is correct
9 Correct 29 ms 59040 KB Output is correct
10 Correct 31 ms 58996 KB Output is correct
11 Correct 29 ms 58984 KB Output is correct
12 Correct 28 ms 58964 KB Output is correct
13 Correct 32 ms 59120 KB Output is correct
14 Correct 27 ms 58916 KB Output is correct
15 Correct 28 ms 58984 KB Output is correct
16 Correct 28 ms 58960 KB Output is correct
17 Correct 27 ms 58924 KB Output is correct
18 Correct 28 ms 58936 KB Output is correct
19 Correct 33 ms 58940 KB Output is correct
20 Correct 28 ms 58920 KB Output is correct
21 Correct 28 ms 58940 KB Output is correct
22 Correct 28 ms 59092 KB Output is correct
23 Correct 28 ms 58992 KB Output is correct
24 Correct 28 ms 59020 KB Output is correct
25 Correct 29 ms 59056 KB Output is correct
26 Incorrect 29 ms 58996 KB 3rd lines differ - on the 1st token, expected: '12988', found: '13018'
27 Halted 0 ms 0 KB -

Subtask #3
0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 28 ms 58936 KB Output is correct
3 Correct 29 ms 58964 KB Output is correct
4 Correct 31 ms 58956 KB Output is correct
5 Correct 27 ms 59020 KB Output is correct
6 Correct 28 ms 58956 KB Output is correct
7 Correct 28 ms 58916 KB Output is correct
8 Correct 28 ms 58964 KB Output is correct
9 Correct 29 ms 59040 KB Output is correct
10 Correct 31 ms 58996 KB Output is correct
11 Correct 29 ms 58984 KB Output is correct
12 Correct 28 ms 58964 KB Output is correct
13 Correct 32 ms 59120 KB Output is correct
14 Correct 27 ms 58916 KB Output is correct
15 Correct 28 ms 58984 KB Output is correct
16 Correct 28 ms 58960 KB Output is correct
17 Correct 27 ms 58924 KB Output is correct
18 Correct 28 ms 58936 KB Output is correct
19 Correct 33 ms 58940 KB Output is correct
20 Correct 28 ms 58920 KB Output is correct
21 Correct 28 ms 58940 KB Output is correct
22 Correct 28 ms 59092 KB Output is correct
23 Correct 28 ms 58992 KB Output is correct
24 Correct 28 ms 59020 KB Output is correct
25 Correct 29 ms 59056 KB Output is correct
26 Incorrect 29 ms 58996 KB 3rd lines differ - on the 1st token, expected: '12988', found: '13018'
27 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 31 ms 59092 KB 3rd lines differ - on the 1st token, expected: '3304', found: '2744'
2 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 58964 KB Output is correct
2 Correct 28 ms 58936 KB Output is correct
3 Correct 29 ms 58964 KB Output is correct
4 Correct 31 ms 58956 KB Output is correct
5 Correct 27 ms 59020 KB Output is correct
6 Correct 28 ms 58956 KB Output is correct
7 Correct 28 ms 58916 KB Output is correct
8 Correct 28 ms 58964 KB Output is correct
9 Correct 29 ms 59040 KB Output is correct
10 Correct 31 ms 58996 KB Output is correct
11 Correct 29 ms 58984 KB Output is correct
12 Correct 28 ms 58964 KB Output is correct
13 Correct 32 ms 59120 KB Output is correct
14 Correct 27 ms 58916 KB Output is correct
15 Correct 28 ms 58984 KB Output is correct
16 Correct 28 ms 58960 KB Output is correct
17 Correct 27 ms 58924 KB Output is correct
18 Correct 28 ms 58936 KB Output is correct
19 Correct 33 ms 58940 KB Output is correct
20 Correct 28 ms 58920 KB Output is correct
21 Correct 28 ms 58940 KB Output is correct
22 Correct 28 ms 59092 KB Output is correct
23 Correct 28 ms 58992 KB Output is correct
24 Correct 28 ms 59020 KB Output is correct
25 Correct 29 ms 59056 KB Output is correct
26 Incorrect 29 ms 58996 KB 3rd lines differ - on the 1st token, expected: '12988', found: '13018'
27 Halted 0 ms 0 KB -