oj.uz

Submission #788183

# Submission time Handle Problem Language Result Execution time Memory
788183 2023-07-19T21:54:40 Z PanosPask Bridges (APIO19_bridges) C++14
100 / 100
 1340 ms 9188 KB 
#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair

using namespace std;

typedef pair<int, int> pi;

struct DSU {
    int size;
    vector<int> rep;
    vector<int> sz;
    stack<int> upd;

    void init(int n) {
        size = n;
        sz.assign(size, 1);
        while (!upd.empty())
            upd.pop();

        rep.resize(size);
        for (int i = 0; i < n; i++)
            rep[i] = i;
    }
    void clear(void) {
        init(size);
    }

    void save(void) {
        upd.push(-1);
    }
    void rollback(void) {
        while (upd.top() != -1) {
            sz[rep[upd.top()]] -= sz[upd.top()];
            rep[upd.top()] = upd.top();

            upd.pop();
        }
        upd.pop();
    }

    int find(int a) {
        while (rep[a] != a)
            a = rep[a];

        return a;
    }
    int component(int a) {
        return sz[find(a)];
    }

    void unite(int a, int b) {
        a = find(a);
        b = find(b);

        if (a == b)
            return;

        if (sz[a] < sz[b])
            swap(a, b);

        upd.push(b);
        sz[a] += sz[b];
        rep[b] = a;

        return;
    }
};

struct Edge {
    int a, b, w;
    int id;

    bool operator < (const Edge& b) {
        return this->w < b.w;
    }
};
struct Update {
    int edge;
    int v;
    int time;

    bool operator < (const Update& b) {
        return this->time < b.time;
    }
};
struct Query {
    int id;
    int s;
    int v;
    int time;

    bool operator < (const Query& b) {
        return this->v < b.v;
    }
};

int N, M, Q;
int BLOCK_SIZE;
vector<Edge> edges;
vector<Edge> original_edges;
vector<bool> changed;
vector<int> ans;

DSU graph;

void process_block(vector<Update>& updates, vector<Query>& queries)
{
    graph.clear();

    sort(queries.rbegin(), queries.rend());
    sort(updates.rbegin(), updates.rend());
    for (auto& u : updates) {
        changed[u.edge] = true;
    }

    int cure = 0;
    for (auto& q : queries) {
        while (cure < M && edges[cure].w >= q.v) {
            if (!changed[edges[cure].id])
                graph.unite(edges[cure].a, edges[cure].b);

            cure++;
        }

        graph.save();
        for (auto& u : updates) {
            if (u.time > q.time)
                continue;
            if (!changed[u.edge])
                continue;

            // mark this edge
            changed[u.edge] = false;
            if (u.v < q.v)
                continue;

            int a = original_edges[u.edge].a;
            int b = original_edges[u.edge].b;
            graph.unite(a, b);
        }
        for (auto& u : updates) {
            if (u.time < q.time)
                continue;
            if (!changed[u.edge])
                continue;

            changed[u.edge] = false;
            int a, b, v;
            a = original_edges[u.edge].a;
            b = original_edges[u.edge].b;
            v = original_edges[u.edge].w;

            if (v < q.v)
                continue;
            graph.unite(a, b);
        }
        for (auto& u : updates) {
            changed[u.edge] = true;
        }

        ans[q.id] = graph.component(q.s);
        graph.rollback();
    }

    for (auto& u : updates) {
        changed[u.edge] = false;
    }
}

int main(void)
{
    scanf("%d %d", &N, &M);

    changed.resize(M);
    graph.init(N);

    for (int i = 0; i < M; i++) {
        int u, v, w;
        scanf("%d %d %d", &u, &v, &w);
        u--; v--;

        edges.push_back({u, v, w, i});
        original_edges.push_back({u, v, w, i});
    }
    edges = original_edges;
    sort(edges.rbegin(), edges.rend());

    scanf("%d", &Q);

    // BLOCK_SIZE = sqrt(Q);
    BLOCK_SIZE = 1000;

    vector<Query> queries;
    vector<Update> updates;
    for (int i = 0; i < Q; i++) {
        int op;
        scanf("%d", &op);

        if (op == 1) {
            int id, v;
            scanf("%d %d", &id, &v);
            id--;

            updates.push_back({id, v, i});
        }
        else {
            int s, v;
            scanf("%d %d", &s, &v);
            s--;

            queries.push_back({(int)ans.size(), s, v, i});
            ans.push_back(0);
        }

        if (i % BLOCK_SIZE == BLOCK_SIZE - 1) {
            process_block(updates, queries);

            reverse(updates.begin(), updates.end());
            for (auto& u : updates) {
                original_edges[u.edge].w = u.v;
            }
            edges = original_edges;
            sort(edges.rbegin(), edges.rend());

            updates.clear();
            queries.clear();
        }
    }
    process_block(updates, queries);

    for (int i = 0; i < ans.size(); i++) {
        printf("%d\n", ans[i]);
    }

    return 0;
}

Compilation message

bridges.cpp: In function 'int main()':
bridges.cpp:232:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  232 |     for (int i = 0; i < ans.size(); i++) {
      |                     ~~^~~~~~~~~~~~
bridges.cpp:173:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  173 |     scanf("%d %d", &N, &M);
      |     ~~~~~^~~~~~~~~~~~~~~~~
bridges.cpp:180:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  180 |         scanf("%d %d %d", &u, &v, &w);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bridges.cpp:189:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  189 |     scanf("%d", &Q);
      |     ~~~~~^~~~~~~~~~
bridges.cpp:198:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  198 |         scanf("%d", &op);
      |         ~~~~~^~~~~~~~~~~
bridges.cpp:202:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  202 |             scanf("%d %d", &id, &v);
      |             ~~~~~^~~~~~~~~~~~~~~~~~
bridges.cpp:209:18: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  209 |             scanf("%d %d", &s, &v);
      |             ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 23 ms 568 KB Output is correct
4 Correct 4 ms 572 KB Output is correct
5 Correct 19 ms 468 KB Output is correct
6 Correct 17 ms 436 KB Output is correct
7 Correct 17 ms 468 KB Output is correct
8 Correct 18 ms 536 KB Output is correct
9 Correct 16 ms 468 KB Output is correct
10 Correct 18 ms 528 KB Output is correct
11 Correct 18 ms 508 KB Output is correct
12 Correct 18 ms 520 KB Output is correct
13 Correct 22 ms 508 KB Output is correct
14 Correct 21 ms 508 KB Output is correct
15 Correct 19 ms 508 KB Output is correct
16 Correct 17 ms 452 KB Output is correct
17 Correct 17 ms 424 KB Output is correct

Subtask #2
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 753 ms 3496 KB Output is correct
2 Correct 812 ms 3336 KB Output is correct
3 Correct 765 ms 3292 KB Output is correct
4 Correct 882 ms 3320 KB Output is correct
5 Correct 870 ms 3304 KB Output is correct
6 Correct 1340 ms 3484 KB Output is correct
7 Correct 1337 ms 3472 KB Output is correct
8 Correct 1237 ms 3400 KB Output is correct
9 Correct 32 ms 1232 KB Output is correct
10 Correct 638 ms 3304 KB Output is correct
11 Correct 609 ms 3356 KB Output is correct
12 Correct 670 ms 4112 KB Output is correct
13 Correct 759 ms 2812 KB Output is correct

Subtask #3
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 587 ms 2636 KB Output is correct
2 Correct 401 ms 1460 KB Output is correct
3 Correct 640 ms 2588 KB Output is correct
4 Correct 560 ms 2584 KB Output is correct
5 Correct 32 ms 1280 KB Output is correct
6 Correct 620 ms 2692 KB Output is correct
7 Correct 541 ms 2520 KB Output is correct
8 Correct 493 ms 2504 KB Output is correct
9 Correct 403 ms 2812 KB Output is correct
10 Correct 406 ms 2744 KB Output is correct
11 Correct 424 ms 2064 KB Output is correct
12 Correct 397 ms 2216 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 971 ms 5856 KB Output is correct
2 Correct 38 ms 1204 KB Output is correct
3 Correct 137 ms 3832 KB Output is correct
4 Correct 64 ms 3860 KB Output is correct
5 Correct 541 ms 5776 KB Output is correct
6 Correct 985 ms 5600 KB Output is correct
7 Correct 581 ms 5628 KB Output is correct
8 Correct 460 ms 3832 KB Output is correct
9 Correct 473 ms 3940 KB Output is correct
10 Correct 467 ms 3956 KB Output is correct
11 Correct 729 ms 4592 KB Output is correct
12 Correct 722 ms 4668 KB Output is correct
13 Correct 741 ms 4964 KB Output is correct
14 Correct 495 ms 5732 KB Output is correct
15 Correct 519 ms 5708 KB Output is correct
16 Correct 1014 ms 5540 KB Output is correct
17 Correct 1010 ms 5552 KB Output is correct
18 Correct 1004 ms 9188 KB Output is correct
19 Correct 1029 ms 9092 KB Output is correct
20 Correct 846 ms 8072 KB Output is correct
21 Correct 857 ms 8060 KB Output is correct
22 Correct 1008 ms 8876 KB Output is correct
23 Correct 569 ms 6924 KB Output is correct

Subtask #5
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 753 ms 3496 KB Output is correct
2 Correct 812 ms 3336 KB Output is correct
3 Correct 765 ms 3292 KB Output is correct
4 Correct 882 ms 3320 KB Output is correct
5 Correct 870 ms 3304 KB Output is correct
6 Correct 1340 ms 3484 KB Output is correct
7 Correct 1337 ms 3472 KB Output is correct
8 Correct 1237 ms 3400 KB Output is correct
9 Correct 32 ms 1232 KB Output is correct
10 Correct 638 ms 3304 KB Output is correct
11 Correct 609 ms 3356 KB Output is correct
12 Correct 670 ms 4112 KB Output is correct
13 Correct 759 ms 2812 KB Output is correct
14 Correct 587 ms 2636 KB Output is correct
15 Correct 401 ms 1460 KB Output is correct
16 Correct 640 ms 2588 KB Output is correct
17 Correct 560 ms 2584 KB Output is correct
18 Correct 32 ms 1280 KB Output is correct
19 Correct 620 ms 2692 KB Output is correct
20 Correct 541 ms 2520 KB Output is correct
21 Correct 493 ms 2504 KB Output is correct
22 Correct 403 ms 2812 KB Output is correct
23 Correct 406 ms 2744 KB Output is correct
24 Correct 424 ms 2064 KB Output is correct
25 Correct 397 ms 2216 KB Output is correct
26 Correct 743 ms 3324 KB Output is correct
27 Correct 1008 ms 3444 KB Output is correct
28 Correct 810 ms 3372 KB Output is correct
29 Correct 661 ms 3196 KB Output is correct
30 Correct 926 ms 3300 KB Output is correct
31 Correct 951 ms 3420 KB Output is correct
32 Correct 950 ms 3372 KB Output is correct
33 Correct 798 ms 3288 KB Output is correct
34 Correct 844 ms 3304 KB Output is correct
35 Correct 810 ms 3300 KB Output is correct
36 Correct 672 ms 3224 KB Output is correct
37 Correct 669 ms 3300 KB Output is correct
38 Correct 663 ms 3300 KB Output is correct
39 Correct 529 ms 3720 KB Output is correct
40 Correct 530 ms 3800 KB Output is correct
41 Correct 529 ms 3728 KB Output is correct
42 Correct 530 ms 2868 KB Output is correct
43 Correct 540 ms 2960 KB Output is correct
44 Correct 533 ms 2864 KB Output is correct

Subtask #6
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 23 ms 568 KB Output is correct
4 Correct 4 ms 572 KB Output is correct
5 Correct 19 ms 468 KB Output is correct
6 Correct 17 ms 436 KB Output is correct
7 Correct 17 ms 468 KB Output is correct
8 Correct 18 ms 536 KB Output is correct
9 Correct 16 ms 468 KB Output is correct
10 Correct 18 ms 528 KB Output is correct
11 Correct 18 ms 508 KB Output is correct
12 Correct 18 ms 520 KB Output is correct
13 Correct 22 ms 508 KB Output is correct
14 Correct 21 ms 508 KB Output is correct
15 Correct 19 ms 508 KB Output is correct
16 Correct 17 ms 452 KB Output is correct
17 Correct 17 ms 424 KB Output is correct
18 Correct 753 ms 3496 KB Output is correct
19 Correct 812 ms 3336 KB Output is correct
20 Correct 765 ms 3292 KB Output is correct
21 Correct 882 ms 3320 KB Output is correct
22 Correct 870 ms 3304 KB Output is correct
23 Correct 1340 ms 3484 KB Output is correct
24 Correct 1337 ms 3472 KB Output is correct
25 Correct 1237 ms 3400 KB Output is correct
26 Correct 32 ms 1232 KB Output is correct
27 Correct 638 ms 3304 KB Output is correct
28 Correct 609 ms 3356 KB Output is correct
29 Correct 670 ms 4112 KB Output is correct
30 Correct 759 ms 2812 KB Output is correct
31 Correct 587 ms 2636 KB Output is correct
32 Correct 401 ms 1460 KB Output is correct
33 Correct 640 ms 2588 KB Output is correct
34 Correct 560 ms 2584 KB Output is correct
35 Correct 32 ms 1280 KB Output is correct
36 Correct 620 ms 2692 KB Output is correct
37 Correct 541 ms 2520 KB Output is correct
38 Correct 493 ms 2504 KB Output is correct
39 Correct 403 ms 2812 KB Output is correct
40 Correct 406 ms 2744 KB Output is correct
41 Correct 424 ms 2064 KB Output is correct
42 Correct 397 ms 2216 KB Output is correct
43 Correct 971 ms 5856 KB Output is correct
44 Correct 38 ms 1204 KB Output is correct
45 Correct 137 ms 3832 KB Output is correct
46 Correct 64 ms 3860 KB Output is correct
47 Correct 541 ms 5776 KB Output is correct
48 Correct 985 ms 5600 KB Output is correct
49 Correct 581 ms 5628 KB Output is correct
50 Correct 460 ms 3832 KB Output is correct
51 Correct 473 ms 3940 KB Output is correct
52 Correct 467 ms 3956 KB Output is correct
53 Correct 729 ms 4592 KB Output is correct
54 Correct 722 ms 4668 KB Output is correct
55 Correct 741 ms 4964 KB Output is correct
56 Correct 495 ms 5732 KB Output is correct
57 Correct 519 ms 5708 KB Output is correct
58 Correct 1014 ms 5540 KB Output is correct
59 Correct 1010 ms 5552 KB Output is correct
60 Correct 1004 ms 9188 KB Output is correct
61 Correct 1029 ms 9092 KB Output is correct
62 Correct 846 ms 8072 KB Output is correct
63 Correct 857 ms 8060 KB Output is correct
64 Correct 1008 ms 8876 KB Output is correct
65 Correct 569 ms 6924 KB Output is correct
66 Correct 743 ms 3324 KB Output is correct
67 Correct 1008 ms 3444 KB Output is correct
68 Correct 810 ms 3372 KB Output is correct
69 Correct 661 ms 3196 KB Output is correct
70 Correct 926 ms 3300 KB Output is correct
71 Correct 951 ms 3420 KB Output is correct
72 Correct 950 ms 3372 KB Output is correct
73 Correct 798 ms 3288 KB Output is correct
74 Correct 844 ms 3304 KB Output is correct
75 Correct 810 ms 3300 KB Output is correct
76 Correct 672 ms 3224 KB Output is correct
77 Correct 669 ms 3300 KB Output is correct
78 Correct 663 ms 3300 KB Output is correct
79 Correct 529 ms 3720 KB Output is correct
80 Correct 530 ms 3800 KB Output is correct
81 Correct 529 ms 3728 KB Output is correct
82 Correct 530 ms 2868 KB Output is correct
83 Correct 540 ms 2960 KB Output is correct
84 Correct 533 ms 2864 KB Output is correct
85 Correct 1265 ms 8460 KB Output is correct
86 Correct 138 ms 5344 KB Output is correct
87 Correct 85 ms 5544 KB Output is correct
88 Correct 796 ms 7008 KB Output is correct
89 Correct 1270 ms 8696 KB Output is correct
90 Correct 848 ms 7136 KB Output is correct
91 Correct 872 ms 5708 KB Output is correct
92 Correct 838 ms 5728 KB Output is correct
93 Correct 1154 ms 5732 KB Output is correct
94 Correct 1082 ms 7024 KB Output is correct
95 Correct 1050 ms 7104 KB Output is correct
96 Correct 1169 ms 7000 KB Output is correct
97 Correct 634 ms 7624 KB Output is correct
98 Correct 666 ms 6480 KB Output is correct
99 Correct 1282 ms 8372 KB Output is correct
100 Correct 1287 ms 8400 KB Output is correct
101 Correct 1290 ms 8520 KB Output is correct
102 Correct 1320 ms 8540 KB Output is correct
103 Correct 1261 ms 7528 KB Output is correct
104 Correct 1268 ms 7500 KB Output is correct
105 Correct 1042 ms 7104 KB Output is correct
106 Correct 847 ms 6512 KB Output is correct
107 Correct 985 ms 8184 KB Output is correct
108 Correct 1281 ms 8200 KB Output is correct
109 Correct 882 ms 6116 KB Output is correct