oj.uz

Submission #1058312

# Submission time Handle Problem Language Result Execution time Memory
1058312 2024-08-14T09:18:22 Z vjudge1 Fountain Parks (IOI21_parks) C++17
15 / 100
 1237 ms 162748 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);
                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:133:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  133 |     for(int i = 0; i < B.size(); ++i)
      |                    ~~^~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory 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 0 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 348 KB Output is correct
9 Correct 442 ms 81208 KB Output is correct
10 Correct 27 ms 8408 KB Output is correct
11 Correct 160 ms 44056 KB Output is correct
12 Correct 42 ms 12324 KB Output is correct
13 Correct 101 ms 23424 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 5 ms 1472 KB Output is correct
16 Correct 411 ms 81364 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory 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 0 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 348 KB Output is correct
9 Correct 442 ms 81208 KB Output is correct
10 Correct 27 ms 8408 KB Output is correct
11 Correct 160 ms 44056 KB Output is correct
12 Correct 42 ms 12324 KB Output is correct
13 Correct 101 ms 23424 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 5 ms 1472 KB Output is correct
16 Correct 411 ms 81364 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 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1206 ms 147688 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 1116 KB Output is correct
26 Correct 9 ms 1756 KB Output is correct
27 Correct 15 ms 2392 KB Output is correct
28 Correct 382 ms 58716 KB Output is correct
29 Correct 620 ms 89608 KB Output is correct
30 Correct 857 ms 117432 KB Output is correct
31 Correct 1237 ms 147436 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 436 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 344 KB Output is correct
43 Correct 4 ms 1112 KB Output is correct
44 Correct 8 ms 1808 KB Output is correct
45 Correct 424 ms 65212 KB Output is correct
46 Correct 731 ms 95372 KB Output is correct
47 Correct 664 ms 96288 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory 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 0 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 348 KB Output is correct
9 Correct 442 ms 81208 KB Output is correct
10 Correct 27 ms 8408 KB Output is correct
11 Correct 160 ms 44056 KB Output is correct
12 Correct 42 ms 12324 KB Output is correct
13 Correct 101 ms 23424 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 5 ms 1472 KB Output is correct
16 Correct 411 ms 81364 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 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1206 ms 147688 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 1116 KB Output is correct
26 Correct 9 ms 1756 KB Output is correct
27 Correct 15 ms 2392 KB Output is correct
28 Correct 382 ms 58716 KB Output is correct
29 Correct 620 ms 89608 KB Output is correct
30 Correct 857 ms 117432 KB Output is correct
31 Correct 1237 ms 147436 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 436 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 344 KB Output is correct
43 Correct 4 ms 1112 KB Output is correct
44 Correct 8 ms 1808 KB Output is correct
45 Correct 424 ms 65212 KB Output is correct
46 Correct 731 ms 95372 KB Output is correct
47 Correct 664 ms 96288 KB Output is correct
48 Correct 0 ms 344 KB Output is correct
49 Correct 0 ms 504 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 1216 ms 158540 KB a[4] = 16781314 is not an odd integer
56 Halted 0 ms 0 KB -

Subtask #4
0 / 20.0

# Verdict Execution time Memory 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 0 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 348 KB Output is correct
9 Correct 442 ms 81208 KB Output is correct
10 Correct 27 ms 8408 KB Output is correct
11 Correct 160 ms 44056 KB Output is correct
12 Correct 42 ms 12324 KB Output is correct
13 Correct 101 ms 23424 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 5 ms 1472 KB Output is correct
16 Correct 411 ms 81364 KB Output is correct
17 Correct 0 ms 344 KB Output is correct
18 Correct 1 ms 344 KB Output is correct
19 Correct 0 ms 412 KB Output is correct
20 Incorrect 714 ms 78892 KB Solution announced impossible, but it is possible.
21 Halted 0 ms 0 KB -

Subtask #5
0 / 20.0

# Verdict Execution time Memory 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 0 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 348 KB Output is correct
9 Correct 442 ms 81208 KB Output is correct
10 Correct 27 ms 8408 KB Output is correct
11 Correct 160 ms 44056 KB Output is correct
12 Correct 42 ms 12324 KB Output is correct
13 Correct 101 ms 23424 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 5 ms 1472 KB Output is correct
16 Correct 411 ms 81364 KB Output is correct
17 Correct 1072 ms 162748 KB Output is correct
18 Correct 1046 ms 162404 KB Output is correct
19 Incorrect 770 ms 81324 KB Solution announced impossible, but it is possible.
20 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory 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 0 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 348 KB Output is correct
9 Correct 442 ms 81208 KB Output is correct
10 Correct 27 ms 8408 KB Output is correct
11 Correct 160 ms 44056 KB Output is correct
12 Correct 42 ms 12324 KB Output is correct
13 Correct 101 ms 23424 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 5 ms 1472 KB Output is correct
16 Correct 411 ms 81364 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 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1206 ms 147688 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 1116 KB Output is correct
26 Correct 9 ms 1756 KB Output is correct
27 Correct 15 ms 2392 KB Output is correct
28 Correct 382 ms 58716 KB Output is correct
29 Correct 620 ms 89608 KB Output is correct
30 Correct 857 ms 117432 KB Output is correct
31 Correct 1237 ms 147436 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 436 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 344 KB Output is correct
43 Correct 4 ms 1112 KB Output is correct
44 Correct 8 ms 1808 KB Output is correct
45 Correct 424 ms 65212 KB Output is correct
46 Correct 731 ms 95372 KB Output is correct
47 Correct 664 ms 96288 KB Output is correct
48 Correct 0 ms 344 KB Output is correct
49 Correct 0 ms 504 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 1216 ms 158540 KB a[4] = 16781314 is not an odd integer
56 Halted 0 ms 0 KB -