답안 #1058321

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1058321 2024-08-14T09:21:28 Z vjudge1 분수 공원 (IOI21_parks) C++17
15 / 100
1138 ms 161680 KB
#include "parks.h"
#include <bits/stdc++.h>

using namespace std;

using vi = vector<int>;
using ii = pair<int, int>;

int DX[] = {-1, 0, 1, 0};
int DY[] = {0, 1, 0, -1};

struct DSU {
    int nrc;
    vi e;
    DSU(int n) : nrc(n), e(n, -1) {}
    int repr(int u) {
        while(e[u] >= 0) u = e[u];
        return u;
    }

    bool same(int u, int v) { return repr(u) == repr(v); }

    void join(int u, int v) {
        u = repr(u);
        v = repr(v);
        if(u == v) return;
        --nrc;
        if(e[u] >= e[v]) swap(u, v);
        e[u] += e[v];
        e[v] = u;
    }
};

vi solve_assign(int m, int len, vector<vector<ii> > &G0, bool &ok) {
    /// will return a vector of len elements, with the id of the bench assigned to path i
    vector<set<ii> > G(m);
    for(int i = 0; i < m; ++i) {
        for(auto it : G0[i]) G[i].insert(it);
    }
   // printf("m=%d len=%d\n", m, len);
   // for(int i = 0; i < m; ++i) {
   //     printf("G[%d]: ", i);
   //     for(auto [a, b] : G[i]) printf("(%d, %d) ", a, b);
   //     printf("\n");
   // }
   // printf("\n");
    vi Re(len, -1);
    
    set<int> noduri_singure;
    for(int i = 0; i < m; ++i) {
        if(G[i].size() == 1) {
            noduri_singure.insert(i);
        }
    }
    while(!noduri_singure.empty()) {
        auto u = *noduri_singure.begin();
        noduri_singure.erase(u);
        if(G[u].empty()) continue;

        /// am muchia u<->v, care se refera la drumul cul
        auto [v, cul] = *G[u].begin(); 

        Re[cul] = u;
        G[v].erase({u, cul});
        G[u].clear();
        if(G[v].size() == 1) noduri_singure.insert(v);
    }


    ///fiecare nod are outdeg > 1 acum
    ///ar trebuii sa fi ramas doar cu un ciclu

    vi viz(m, 0);
    function<void(int, int)> dfs = [&](int u, int p) {
        for(auto [v, cul] : G[u]) {
            if(v == p) continue;
            if(!viz[v]) {
                viz[v] = 1;
                Re[cul] = v;
                dfs(v, u);
            }
            if(viz[u]) break;
        }
    };
    for(int i = 0; i < m; ++i) {
        if(G[i].size() > 1) {
            dfs(i, -1);
            break;
        }
    }
  //  printf("Re: ");
  //  for(auto it : Re) {
  //      printf("%d ", it);
  //  }
  //  printf("\n");
    return Re;
}

int construct_roads(vi x, vi y) {
    int n = (int)x.size();
    map<ii, int> Id;
    for(int i = 0; i < n; ++i)
        Id[ii{x[i], y[i]}] = i;
    auto get_bs_coord = [&](int u, int v) -> pair<ii, ii> {
        int x1 = x[u], y1 = y[u], x2 = x[v], y2 = y[v];
        int xcm = (x1 + x2) / 2, ycm = (y1 + y2) / 2;
        int dx = 2 - abs(x1 - x2), dy = 2 - abs(y1 - y2);
        return make_pair(ii{xcm + dx / 2, ycm + dy / 2}, ii{xcm - dx / 2, ycm - dy / 2});
    };
    vector<ii> B;
    for(int i = 0; i < n; ++i) {
        for(int d = 0; d < 4; ++d) {
            int nx = x[i] + DX[d] * 2, ny = y[i] + DY[d] * 2;
            if(Id.count({nx, ny})) {
                int u = Id[ii{nx, ny}];
                auto [a, b] = get_bs_coord(i, u);
                assert(a.first & 1);
                assert(a.second & 1);
                assert(b.first & 1);
                assert(b.second & 1);
                B.push_back(a);
                B.push_back(b);
            }
        }
    }

    sort(B.begin(), B.end());
    B.resize(unique(B.begin(), B.end()) - B.begin());

    map<ii, int> BenchId;
    int m = (int)B.size();

    vector<vi> L(n); /// graful pe fantani
    vector<ii> E; // edges
    set<ii> SetEdges;
    vector<vector<ii> > G(m); /// graful pe banci
    for(int i = 0; i < B.size(); ++i)
        BenchId[B[i]] = i;
    
    auto get_bs_id = [&](int u, int v) {
        auto [a, b] = get_bs_coord(u, v);
        return ii{BenchId[a], BenchId[b]};
    };

    vector<ii> DupaY;
    for(int i = 0; i < n; ++i)
        DupaY.push_back({y[i], i});
    sort(DupaY.begin(), DupaY.end());

    vi Speciale = {DupaY[0].second};

    DSU UF(n);

    auto add_edge = [&](int u, int v) {
        if(SetEdges.count({u, v})) return;
        SetEdges.insert({u, v});
        SetEdges.insert({v, u});
        auto [a, b] = get_bs_id(u, v);
        G[a].push_back({b, E.size()});
        G[b].push_back({a, E.size()});
        L[u].push_back(v);
        L[v].push_back(u);
        E.push_back({u, v});
        UF.join(u, v);
    };

    for(int i = 1; i < n; ++i) {
        int u = DupaY[i - 1].second, v = DupaY[i].second;
        if(y[u] != y[v] || abs(x[u] - x[v]) > 2) Speciale.push_back(v);
        else add_edge(u, v);
    }

    for(auto it : Speciale) {
        for(int d = 0; d < 4; ++d) {
            int nx = x[it] + DX[d] * 2, ny = y[it] + DY[d] * 2;
            if(Id.count({nx, ny})) {
                int u = Id[ii{nx, ny}];
                add_edge(it, u);
            }
        }
    }

    if(UF.nrc != 1) return 0;

   // printf("muchile pe fantani:\n");
   // for(auto [u, v] : E) {
   //     printf("%d %d\n", u, v);
   // }
   // printf("\n");

    bool ok = 1;
    auto Re = solve_assign(m, E.size(), G, ok);
    if(!ok) return 0;

    int len = E.size();
    vi U(len), V(len), RA(len), RB(len);
    for(int i = 0; i < len; ++i) {
        tie(U[i], V[i]) = E[i];
        int id = Re[i];
        tie(RA[i], RB[i]) = B[id];
    }

    build(U, V, RA, RB);
    return 1;
}

Compilation message

parks.cpp: In function 'int construct_roads(vi, vi)':
parks.cpp:137:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  137 |     for(int i = 0; i < B.size(); ++i)
      |                    ~~^~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 412 ms 80948 KB Output is correct
10 Correct 23 ms 8408 KB Output is correct
11 Correct 147 ms 43460 KB Output is correct
12 Correct 34 ms 12236 KB Output is correct
13 Correct 120 ms 23168 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 5 ms 1372 KB Output is correct
16 Correct 403 ms 80552 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 412 ms 80948 KB Output is correct
10 Correct 23 ms 8408 KB Output is correct
11 Correct 147 ms 43460 KB Output is correct
12 Correct 34 ms 12236 KB Output is correct
13 Correct 120 ms 23168 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 5 ms 1372 KB Output is correct
16 Correct 403 ms 80552 KB Output is correct
17 Correct 0 ms 344 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1104 ms 145744 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 1116 KB Output is correct
26 Correct 6 ms 1756 KB Output is correct
27 Correct 11 ms 2300 KB Output is correct
28 Correct 343 ms 58432 KB Output is correct
29 Correct 548 ms 88764 KB Output is correct
30 Correct 748 ms 116420 KB Output is correct
31 Correct 1022 ms 146868 KB Output is correct
32 Correct 0 ms 348 KB Output is correct
33 Correct 0 ms 348 KB Output is correct
34 Correct 0 ms 348 KB Output is correct
35 Correct 0 ms 348 KB Output is correct
36 Correct 0 ms 348 KB Output is correct
37 Correct 0 ms 348 KB Output is correct
38 Correct 0 ms 348 KB Output is correct
39 Correct 0 ms 348 KB Output is correct
40 Correct 0 ms 348 KB Output is correct
41 Correct 0 ms 348 KB Output is correct
42 Correct 0 ms 348 KB Output is correct
43 Correct 4 ms 1116 KB Output is correct
44 Correct 6 ms 1628 KB Output is correct
45 Correct 384 ms 64936 KB Output is correct
46 Correct 575 ms 93888 KB Output is correct
47 Correct 603 ms 93604 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 412 ms 80948 KB Output is correct
10 Correct 23 ms 8408 KB Output is correct
11 Correct 147 ms 43460 KB Output is correct
12 Correct 34 ms 12236 KB Output is correct
13 Correct 120 ms 23168 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 5 ms 1372 KB Output is correct
16 Correct 403 ms 80552 KB Output is correct
17 Correct 0 ms 344 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1104 ms 145744 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 1116 KB Output is correct
26 Correct 6 ms 1756 KB Output is correct
27 Correct 11 ms 2300 KB Output is correct
28 Correct 343 ms 58432 KB Output is correct
29 Correct 548 ms 88764 KB Output is correct
30 Correct 748 ms 116420 KB Output is correct
31 Correct 1022 ms 146868 KB Output is correct
32 Correct 0 ms 348 KB Output is correct
33 Correct 0 ms 348 KB Output is correct
34 Correct 0 ms 348 KB Output is correct
35 Correct 0 ms 348 KB Output is correct
36 Correct 0 ms 348 KB Output is correct
37 Correct 0 ms 348 KB Output is correct
38 Correct 0 ms 348 KB Output is correct
39 Correct 0 ms 348 KB Output is correct
40 Correct 0 ms 348 KB Output is correct
41 Correct 0 ms 348 KB Output is correct
42 Correct 0 ms 348 KB Output is correct
43 Correct 4 ms 1116 KB Output is correct
44 Correct 6 ms 1628 KB Output is correct
45 Correct 384 ms 64936 KB Output is correct
46 Correct 575 ms 93888 KB Output is correct
47 Correct 603 ms 93604 KB Output is correct
48 Correct 0 ms 344 KB Output is correct
49 Correct 0 ms 348 KB Output is correct
50 Correct 0 ms 348 KB Output is correct
51 Correct 0 ms 348 KB Output is correct
52 Correct 0 ms 348 KB Output is correct
53 Correct 0 ms 348 KB Output is correct
54 Correct 0 ms 348 KB Output is correct
55 Incorrect 1089 ms 156784 KB a[4] = 16781314 is not an odd integer
56 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 412 ms 80948 KB Output is correct
10 Correct 23 ms 8408 KB Output is correct
11 Correct 147 ms 43460 KB Output is correct
12 Correct 34 ms 12236 KB Output is correct
13 Correct 120 ms 23168 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 5 ms 1372 KB Output is correct
16 Correct 403 ms 80552 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Incorrect 686 ms 77884 KB Solution announced impossible, but it is possible.
21 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 412 ms 80948 KB Output is correct
10 Correct 23 ms 8408 KB Output is correct
11 Correct 147 ms 43460 KB Output is correct
12 Correct 34 ms 12236 KB Output is correct
13 Correct 120 ms 23168 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 5 ms 1372 KB Output is correct
16 Correct 403 ms 80552 KB Output is correct
17 Correct 1138 ms 161680 KB Output is correct
18 Correct 1037 ms 161668 KB Output is correct
19 Incorrect 800 ms 80124 KB Solution announced impossible, but it is possible.
20 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 344 KB Output is correct
9 Correct 412 ms 80948 KB Output is correct
10 Correct 23 ms 8408 KB Output is correct
11 Correct 147 ms 43460 KB Output is correct
12 Correct 34 ms 12236 KB Output is correct
13 Correct 120 ms 23168 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 5 ms 1372 KB Output is correct
16 Correct 403 ms 80552 KB Output is correct
17 Correct 0 ms 344 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1104 ms 145744 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 1116 KB Output is correct
26 Correct 6 ms 1756 KB Output is correct
27 Correct 11 ms 2300 KB Output is correct
28 Correct 343 ms 58432 KB Output is correct
29 Correct 548 ms 88764 KB Output is correct
30 Correct 748 ms 116420 KB Output is correct
31 Correct 1022 ms 146868 KB Output is correct
32 Correct 0 ms 348 KB Output is correct
33 Correct 0 ms 348 KB Output is correct
34 Correct 0 ms 348 KB Output is correct
35 Correct 0 ms 348 KB Output is correct
36 Correct 0 ms 348 KB Output is correct
37 Correct 0 ms 348 KB Output is correct
38 Correct 0 ms 348 KB Output is correct
39 Correct 0 ms 348 KB Output is correct
40 Correct 0 ms 348 KB Output is correct
41 Correct 0 ms 348 KB Output is correct
42 Correct 0 ms 348 KB Output is correct
43 Correct 4 ms 1116 KB Output is correct
44 Correct 6 ms 1628 KB Output is correct
45 Correct 384 ms 64936 KB Output is correct
46 Correct 575 ms 93888 KB Output is correct
47 Correct 603 ms 93604 KB Output is correct
48 Correct 0 ms 344 KB Output is correct
49 Correct 0 ms 348 KB Output is correct
50 Correct 0 ms 348 KB Output is correct
51 Correct 0 ms 348 KB Output is correct
52 Correct 0 ms 348 KB Output is correct
53 Correct 0 ms 348 KB Output is correct
54 Correct 0 ms 348 KB Output is correct
55 Incorrect 1089 ms 156784 KB a[4] = 16781314 is not an odd integer
56 Halted 0 ms 0 KB -