oj.uz

Submission #155191

# Submission time Handle Problem Language Result Execution time Memory
155191 2019-09-27T00:10:26 Z rama_pang Werewolf (IOI18_werewolf) C++14
100 / 100
 1331 ms 132460 KB 
#include "werewolf.h"
#include <bits/stdc++.h>
using namespace std;

struct disj {
    vector<int> p;

    disj(int n) {
        p.resize(n);
        iota(p.begin(), p.end(), 0);
    }
    
    int par(int n) {
        return (p[n] == n)? n : p[n] = par(p[n]);
    }
};

struct graph {
    vector<vector<int>> G;

    graph(int n) {
        G.resize(n);
    }
    
    inline void add_edge(int a, int b) {
        G[a].emplace_back(b);
    }
    
    void dfs(int n, vector<pair<int, int>> &euler_tour, vector<int> &euler) {
        euler_tour[n].first = euler.size();
        euler.emplace_back(n);
        for (auto &i : G[n]) {
            dfs(i, euler_tour, euler);
        }
        euler_tour[n].second = euler.size() - 1;
    }
};


struct solver {
    struct event {
        int x, y1, y2, type, idx;
        bool operator < (const event &b) const {
            return x < b.x || (x == b.x && type < b.type);
        }   
    };

    struct bit {
        vector<int> tree;
        
        bit() {}

        void init(int n) {
            tree.assign(n + 1, 0);
        }
        
        void upd(int n, int x) {
            for (int i = n + 1; i < tree.size(); i += i&-i) {
                tree[i] += x;
            }
        }
        
        int ask(int n) {
            int res = 0;
            for (int i = n + 1; i > 0; i -= i&-i) {
                res += tree[i];
            }
            return res;
        }
    } bit;

    vector<event> e;;
    
    solver(int n) {
        bit.init(n);
    }
    
    inline void add_point(int x, int y) {
        e.push_back({x, y, -1, 0, -1}); //add point
    }
    
    inline void add_query(int x1, int x2, int y1, int y2, int id) {
        e.push_back({x1, y1, y2, -1, id}); //from
        e.push_back({x2, y1, y2, +1, id}); //to
    }
    
    void line_sweep(vector<int> &res) {
        sort(e.begin(), e.end());
        for (auto &k : e) {
            if (k.type == -1) {
                res[k.idx] -= bit.ask(k.y2) - bit.ask(k.y1 - 1);
            } else if (k.type == 0) {
                bit.upd(k.y1, +1);
            } else if (k.type == +1) {
                res[k.idx] += bit.ask(k.y2) - bit.ask(k.y1 - 1);
            }
        }
    }
};

vector<int> check_validity(int N, vector<int> X, vector<int> Y, 
                           vector<int> S, vector<int> E, 
                           vector<int> L, vector<int> R) {

    int M = X.size(), Q = S.size();
    /* create a rooted tree, such that any node u can reach its subtrees for L and R */
    disj dsL(N), dsR(N);
    graph lowerL(N), upperR(N);
    vector<vector<int>> pending_edgeL(N), pending_edgeR(N);
    vector<vector<int>> binary_liftL(N, vector<int>(20, -1)), binary_liftR(N, vector<int>(20, -1));
    for (int i = 0; i < M; i++) {
        if (X[i] > Y[i]) swap(X[i], Y[i]);
        pending_edgeL[X[i]].emplace_back(Y[i]);
        pending_edgeR[Y[i]].emplace_back(X[i]);
    }
    /* build tree for L, iterating high vertices first (most limited if L is high) */
    for (int i = N - 1; i >= 0; i--) {
        for (auto &j : pending_edgeL[i]) {
            int p = dsL.par(j);
            if (i == p) continue;
            dsL.p[p] = i;
            binary_liftL[p][0] = i;
            lowerL.add_edge(i, p);
        }
    }
    /* do the same for tree R */
    for (int i = 0; i < N; i++) {
        for (auto &j : pending_edgeR[i]) {
            int p = dsR.par(j);
            if (i == p) continue;
            dsR.p[p] = i;
            binary_liftR[p][0] = i;
            upperR.add_edge(i, p);
        }
    }
    /* create euler tour -> represent the graph with intervals */
    vector<pair<int, int>> intervalL(N), intervalR(N);
    vector<int> eulerL, eulerR;
    lowerL.dfs(0, intervalL, eulerL);
    upperR.dfs(N - 1, intervalR, eulerR);
    vector<int> other_name(N);
    for (int i = 0; i < N; i++) {
        other_name[eulerR[i]] = i;
    }
    /* fenwick tree + line sweep technique to solve, decompose if (intervalL[i] == intervalR[j]) add point (i, j), then check for rectangle for each query */
    solver Solver(N);
    for (int i = 0; i < N; i++) {
        Solver.add_point(i, other_name[eulerL[i]]); //get indexes intervalL in intervalR
    }
    /* create binary lifting for each query S and E, find minimum from S and maximum from E (vertex number) */
    for (int j = 1; j < 20; j++) {
        for (int i = 0; i < N; i++) {
            if (binary_liftL[i][j - 1] != -1) binary_liftL[i][j] = binary_liftL[binary_liftL[i][j - 1]][j - 1];
            if (binary_liftR[i][j - 1] != -1) binary_liftR[i][j] = binary_liftR[binary_liftR[i][j - 1]][j - 1];
        }
    }
    for (int i = 0; i < Q; i++) { //get updates, lift S and E with binary lifting
        int s = S[i], e = E[i];
        for (int j = 19; j >= 0; j--) { //binary lifting
            if (binary_liftL[s][j] != -1 && L[i] <= binary_liftL[s][j]) s = binary_liftL[s][j];
            if (binary_liftR[e][j] != -1 && binary_liftR[e][j] <= R[i]) e = binary_liftR[e][j];
        }
        Solver.add_query(intervalL[s].first, intervalL[s].second, intervalR[e].first, intervalR[e].second, i);
    }
    vector<int> res(Q, 0); Solver.line_sweep(res);
    for (int i = 0; i < Q; i++) res[i] = (res[i] > 0);
    return res;
}

Compilation message

werewolf.cpp: In member function 'void solver::bit::upd(int, int)':
werewolf.cpp:58:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int i = n + 1; i < tree.size(); i += i&-i) {
                                 ~~^~~~~~~~~~~~~

Subtask #1
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct

Subtask #2
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 10 ms 2264 KB Output is correct
11 Correct 10 ms 2264 KB Output is correct
12 Correct 10 ms 2264 KB Output is correct
13 Correct 11 ms 2396 KB Output is correct
14 Correct 10 ms 2396 KB Output is correct
15 Correct 12 ms 2396 KB Output is correct

Subtask #3
34.0 / 34.0

# Verdict Execution time Memory Grader output
1 Correct 956 ms 121304 KB Output is correct
2 Correct 1018 ms 123224 KB Output is correct
3 Correct 959 ms 122164 KB Output is correct
4 Correct 920 ms 121544 KB Output is correct
5 Correct 938 ms 121484 KB Output is correct
6 Correct 942 ms 121260 KB Output is correct
7 Correct 968 ms 121288 KB Output is correct
8 Correct 943 ms 123348 KB Output is correct
9 Correct 807 ms 121812 KB Output is correct
10 Correct 778 ms 121424 KB Output is correct
11 Correct 950 ms 121240 KB Output is correct
12 Correct 876 ms 121276 KB Output is correct
13 Correct 1331 ms 132332 KB Output is correct
14 Correct 1107 ms 132204 KB Output is correct
15 Correct 1092 ms 132460 KB Output is correct
16 Correct 1155 ms 132240 KB Output is correct
17 Correct 911 ms 121312 KB Output is correct

Subtask #4
51.0 / 51.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 2 ms 376 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 376 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 10 ms 2264 KB Output is correct
11 Correct 10 ms 2264 KB Output is correct
12 Correct 10 ms 2264 KB Output is correct
13 Correct 11 ms 2396 KB Output is correct
14 Correct 10 ms 2396 KB Output is correct
15 Correct 12 ms 2396 KB Output is correct
16 Correct 956 ms 121304 KB Output is correct
17 Correct 1018 ms 123224 KB Output is correct
18 Correct 959 ms 122164 KB Output is correct
19 Correct 920 ms 121544 KB Output is correct
20 Correct 938 ms 121484 KB Output is correct
21 Correct 942 ms 121260 KB Output is correct
22 Correct 968 ms 121288 KB Output is correct
23 Correct 943 ms 123348 KB Output is correct
24 Correct 807 ms 121812 KB Output is correct
25 Correct 778 ms 121424 KB Output is correct
26 Correct 950 ms 121240 KB Output is correct
27 Correct 876 ms 121276 KB Output is correct
28 Correct 1331 ms 132332 KB Output is correct
29 Correct 1107 ms 132204 KB Output is correct
30 Correct 1092 ms 132460 KB Output is correct
31 Correct 1155 ms 132240 KB Output is correct
32 Correct 911 ms 121312 KB Output is correct
33 Correct 1131 ms 120572 KB Output is correct
34 Correct 390 ms 28648 KB Output is correct
35 Correct 1135 ms 122416 KB Output is correct
36 Correct 1014 ms 121908 KB Output is correct
37 Correct 1150 ms 121788 KB Output is correct
38 Correct 1059 ms 122092 KB Output is correct
39 Correct 1149 ms 128868 KB Output is correct
40 Correct 1258 ms 129120 KB Output is correct
41 Correct 1022 ms 121452 KB Output is correct
42 Correct 1010 ms 121896 KB Output is correct
43 Correct 1288 ms 127200 KB Output is correct
44 Correct 1126 ms 121956 KB Output is correct
45 Correct 1042 ms 129284 KB Output is correct
46 Correct 1028 ms 128800 KB Output is correct
47 Correct 1136 ms 132308 KB Output is correct
48 Correct 1206 ms 132348 KB Output is correct
49 Correct 1150 ms 132276 KB Output is correct
50 Correct 1147 ms 132428 KB Output is correct
51 Correct 1251 ms 128440 KB Output is correct
52 Correct 1225 ms 128468 KB Output is correct