oj.uz

Submission #563629

# Submission time Handle Problem Language Result Execution time Memory
563629 2022-05-17T19:01:54 Z brunovsky Bridges (APIO19_bridges) C++17
100 / 100
 2518 ms 9792 KB 
#include <bits/stdc++.h>
#ifdef LOCAL
#include "code/formatting.hpp"
#else
#define debug(...) (void)0
#endif

using namespace std;

struct disjoint_set_rollback {
    int N, S;
    vector<int> next;
    vector<pair<int, int>> history;

    explicit disjoint_set_rollback(int N = 0) : N(N), S(N), next(N, -1) {}

    void assign(int n) { *this = disjoint_set_rollback(n); }
    void reset() { *this = disjoint_set_rollback(N); }
    bool same(int i, int j) { return find(i) == find(j); }
    bool unit(int i) { return next[i] == -1; }
    bool root(int i) { return next[i] < 0; }
    int size(int i) { return -next[i]; }
    int time() const { return history.size(); }

    void rollback(int t) {
        int i = time();
        while (i > t) {
            i--, next[history[i].first] = history[i].second;
            i--, next[history[i].first] = history[i].second;
            S++;
        }
        history.resize(t);
    }

    int find(int i) {
        while (next[i] >= 0) {
            i = next[i];
        }
        return i;
    }

    bool join(int i, int j) {
        i = find(i);
        j = find(j);
        if (i != j) {
            if (size(i) < size(j)) {
                swap(i, j);
            }
            history.emplace_back(i, next[i]);
            history.emplace_back(j, next[j]);
            next[i] += next[j];
            next[j] = i, S--;
            return true;
        }
        return false;
    }
};

auto filter_pairs(const vector<array<int, 2>>& a) {
    int N = a.size();
    vector<array<int, 2>> b;
    for (int i = 0; i < N; i++) {
        if (i == 0 || a[i][0] != a[i - 1][0]) {
            b.push_back(a[i]);
        }
    }
    return b;
}

int main() {
    ios::sync_with_stdio(false), cin.tie(nullptr);
    int N, M;
    cin >> N >> M;
    vector<array<int, 3>> graph(M);
    for (int i = 0; i < M; i++) {
        int u, v, d;
        cin >> u >> v >> d, u--, v--;
        graph[i] = {d, u, v};
    }

    auto edge_compare = [&](int a, int b) {
        return make_pair(graph[a][0], a) > make_pair(graph[b][0], b);
    };
    set<int, decltype(edge_compare)> edges(edge_compare);
    for (int e = 0; e < M; e++) {
        edges.insert(e);
    }

    int Q;
    cin >> Q;
    vector<array<int, 3>> queries(Q);
    for (int q = 0; q < Q; q++) {
        int t, a, b;
        cin >> t >> a >> b, a--;
        queries[q] = {t, a, b};
    }

    const int B = sqrt(N + M);
    vector<int> ans(Q), weight(M);

    disjoint_set_rollback dsu(N);

    for (int L = 0, R = min(B, Q); L < Q; L = R, R = min(Q, R + B)) {
        vector<int> upds, asks;
        vector<array<int, 2>> bans;
        for (int q = L; q < R; q++) {
            auto [t, a, b] = queries[q];
            if (t == 1) {
                upds.push_back(q);
                bans.push_back({a, q});
                weight[a] = -1;
            } else if (t == 2) {
                asks.push_back(q);
            } else {
                assert(false);
            }
        }

        sort(begin(asks), end(asks), [&](int i, int j) {
            return make_pair(queries[i][2], j) > make_pair(queries[j][2], i);
        });

        sort(begin(bans), end(bans));
        bans = filter_pairs(bans);

        for (auto [e, _] : bans) {
            edges.erase(e);
        }

        auto it = edges.begin();
        int U = upds.size();

        for (int q : asks) {
            auto [tq, s, w] = queries[q];
            while (it != edges.end() && graph[*it][0] >= w) {
                auto [_, a, b] = graph[*it++];
                dsu.join(a, b);
            }
            int time = dsu.time();
            for (int u = 0; u < U && upds[u] < q; u++) {
                auto [_, e, c] = queries[upds[u]];
                weight[e] = c;
            }
            for (auto [e, t] : bans) {
                int c = q < t ? graph[e][0] : weight[e];
                auto [_, a, b] = graph[e];
                if (c >= w) {
                    dsu.join(a, b);
                }
            }
            ans[q] = dsu.size(dsu.find(s));
            dsu.rollback(time);
        }

        for (int q : upds) {
            auto [_, e, w] = queries[q];
            edges.erase(e), graph[e][0] = w, edges.insert(e);
            weight[e] = 0;
        }

        dsu.rollback(0);
    }

    for (int q = 0; q < Q; q++) {
        if (ans[q] > 0) {
            cout << ans[q] << '\n';
        }
    }

    return 0;
}

// sqrt rebuilds

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 16 ms 540 KB Output is correct
4 Correct 3 ms 468 KB Output is correct
5 Correct 8 ms 444 KB Output is correct
6 Correct 7 ms 480 KB Output is correct
7 Correct 8 ms 468 KB Output is correct
8 Correct 9 ms 492 KB Output is correct
9 Correct 8 ms 468 KB Output is correct
10 Correct 8 ms 468 KB Output is correct
11 Correct 9 ms 468 KB Output is correct
12 Correct 9 ms 488 KB Output is correct
13 Correct 10 ms 468 KB Output is correct
14 Correct 9 ms 468 KB Output is correct
15 Correct 10 ms 468 KB Output is correct
16 Correct 8 ms 468 KB Output is correct
17 Correct 8 ms 468 KB Output is correct

Subtask #2
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1198 ms 6356 KB Output is correct
2 Correct 1230 ms 6280 KB Output is correct
3 Correct 1208 ms 6344 KB Output is correct
4 Correct 1203 ms 6344 KB Output is correct
5 Correct 1181 ms 6316 KB Output is correct
6 Correct 1350 ms 6472 KB Output is correct
7 Correct 1359 ms 6396 KB Output is correct
8 Correct 1369 ms 6388 KB Output is correct
9 Correct 32 ms 2124 KB Output is correct
10 Correct 870 ms 6496 KB Output is correct
11 Correct 909 ms 6344 KB Output is correct
12 Correct 1058 ms 6516 KB Output is correct
13 Correct 1174 ms 6264 KB Output is correct

Subtask #3
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 898 ms 4716 KB Output is correct
2 Correct 430 ms 2816 KB Output is correct
3 Correct 941 ms 4864 KB Output is correct
4 Correct 890 ms 4844 KB Output is correct
5 Correct 32 ms 2004 KB Output is correct
6 Correct 940 ms 4932 KB Output is correct
7 Correct 899 ms 4888 KB Output is correct
8 Correct 851 ms 4804 KB Output is correct
9 Correct 784 ms 4964 KB Output is correct
10 Correct 774 ms 4836 KB Output is correct
11 Correct 837 ms 4712 KB Output is correct
12 Correct 803 ms 4712 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 2133 ms 9624 KB Output is correct
2 Correct 30 ms 2004 KB Output is correct
3 Correct 234 ms 6772 KB Output is correct
4 Correct 135 ms 6732 KB Output is correct
5 Correct 1468 ms 9628 KB Output is correct
6 Correct 2000 ms 9624 KB Output is correct
7 Correct 1485 ms 9616 KB Output is correct
8 Correct 965 ms 6344 KB Output is correct
9 Correct 957 ms 6256 KB Output is correct
10 Correct 981 ms 6384 KB Output is correct
11 Correct 1430 ms 7944 KB Output is correct
12 Correct 1496 ms 7952 KB Output is correct
13 Correct 1455 ms 8080 KB Output is correct
14 Correct 1277 ms 9756 KB Output is correct
15 Correct 1379 ms 9792 KB Output is correct
16 Correct 2190 ms 9584 KB Output is correct
17 Correct 2106 ms 9584 KB Output is correct
18 Correct 2095 ms 9604 KB Output is correct
19 Correct 2106 ms 9596 KB Output is correct
20 Correct 1758 ms 8736 KB Output is correct
21 Correct 1706 ms 8724 KB Output is correct
22 Correct 1978 ms 9436 KB Output is correct
23 Correct 1486 ms 8436 KB Output is correct

Subtask #5
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1198 ms 6356 KB Output is correct
2 Correct 1230 ms 6280 KB Output is correct
3 Correct 1208 ms 6344 KB Output is correct
4 Correct 1203 ms 6344 KB Output is correct
5 Correct 1181 ms 6316 KB Output is correct
6 Correct 1350 ms 6472 KB Output is correct
7 Correct 1359 ms 6396 KB Output is correct
8 Correct 1369 ms 6388 KB Output is correct
9 Correct 32 ms 2124 KB Output is correct
10 Correct 870 ms 6496 KB Output is correct
11 Correct 909 ms 6344 KB Output is correct
12 Correct 1058 ms 6516 KB Output is correct
13 Correct 1174 ms 6264 KB Output is correct
14 Correct 898 ms 4716 KB Output is correct
15 Correct 430 ms 2816 KB Output is correct
16 Correct 941 ms 4864 KB Output is correct
17 Correct 890 ms 4844 KB Output is correct
18 Correct 32 ms 2004 KB Output is correct
19 Correct 940 ms 4932 KB Output is correct
20 Correct 899 ms 4888 KB Output is correct
21 Correct 851 ms 4804 KB Output is correct
22 Correct 784 ms 4964 KB Output is correct
23 Correct 774 ms 4836 KB Output is correct
24 Correct 837 ms 4712 KB Output is correct
25 Correct 803 ms 4712 KB Output is correct
26 Correct 1149 ms 6340 KB Output is correct
27 Correct 1366 ms 6348 KB Output is correct
28 Correct 1324 ms 6344 KB Output is correct
29 Correct 1165 ms 6352 KB Output is correct
30 Correct 1349 ms 6352 KB Output is correct
31 Correct 1341 ms 6348 KB Output is correct
32 Correct 1371 ms 6356 KB Output is correct
33 Correct 1235 ms 6344 KB Output is correct
34 Correct 1254 ms 6344 KB Output is correct
35 Correct 1247 ms 6352 KB Output is correct
36 Correct 1123 ms 6264 KB Output is correct
37 Correct 1129 ms 6348 KB Output is correct
38 Correct 1122 ms 6348 KB Output is correct
39 Correct 1027 ms 6344 KB Output is correct
40 Correct 1046 ms 6356 KB Output is correct
41 Correct 1035 ms 6344 KB Output is correct
42 Correct 996 ms 6284 KB Output is correct
43 Correct 1006 ms 6352 KB Output is correct
44 Correct 990 ms 6416 KB Output is correct

Subtask #6
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 16 ms 540 KB Output is correct
4 Correct 3 ms 468 KB Output is correct
5 Correct 8 ms 444 KB Output is correct
6 Correct 7 ms 480 KB Output is correct
7 Correct 8 ms 468 KB Output is correct
8 Correct 9 ms 492 KB Output is correct
9 Correct 8 ms 468 KB Output is correct
10 Correct 8 ms 468 KB Output is correct
11 Correct 9 ms 468 KB Output is correct
12 Correct 9 ms 488 KB Output is correct
13 Correct 10 ms 468 KB Output is correct
14 Correct 9 ms 468 KB Output is correct
15 Correct 10 ms 468 KB Output is correct
16 Correct 8 ms 468 KB Output is correct
17 Correct 8 ms 468 KB Output is correct
18 Correct 1198 ms 6356 KB Output is correct
19 Correct 1230 ms 6280 KB Output is correct
20 Correct 1208 ms 6344 KB Output is correct
21 Correct 1203 ms 6344 KB Output is correct
22 Correct 1181 ms 6316 KB Output is correct
23 Correct 1350 ms 6472 KB Output is correct
24 Correct 1359 ms 6396 KB Output is correct
25 Correct 1369 ms 6388 KB Output is correct
26 Correct 32 ms 2124 KB Output is correct
27 Correct 870 ms 6496 KB Output is correct
28 Correct 909 ms 6344 KB Output is correct
29 Correct 1058 ms 6516 KB Output is correct
30 Correct 1174 ms 6264 KB Output is correct
31 Correct 898 ms 4716 KB Output is correct
32 Correct 430 ms 2816 KB Output is correct
33 Correct 941 ms 4864 KB Output is correct
34 Correct 890 ms 4844 KB Output is correct
35 Correct 32 ms 2004 KB Output is correct
36 Correct 940 ms 4932 KB Output is correct
37 Correct 899 ms 4888 KB Output is correct
38 Correct 851 ms 4804 KB Output is correct
39 Correct 784 ms 4964 KB Output is correct
40 Correct 774 ms 4836 KB Output is correct
41 Correct 837 ms 4712 KB Output is correct
42 Correct 803 ms 4712 KB Output is correct
43 Correct 2133 ms 9624 KB Output is correct
44 Correct 30 ms 2004 KB Output is correct
45 Correct 234 ms 6772 KB Output is correct
46 Correct 135 ms 6732 KB Output is correct
47 Correct 1468 ms 9628 KB Output is correct
48 Correct 2000 ms 9624 KB Output is correct
49 Correct 1485 ms 9616 KB Output is correct
50 Correct 965 ms 6344 KB Output is correct
51 Correct 957 ms 6256 KB Output is correct
52 Correct 981 ms 6384 KB Output is correct
53 Correct 1430 ms 7944 KB Output is correct
54 Correct 1496 ms 7952 KB Output is correct
55 Correct 1455 ms 8080 KB Output is correct
56 Correct 1277 ms 9756 KB Output is correct
57 Correct 1379 ms 9792 KB Output is correct
58 Correct 2190 ms 9584 KB Output is correct
59 Correct 2106 ms 9584 KB Output is correct
60 Correct 2095 ms 9604 KB Output is correct
61 Correct 2106 ms 9596 KB Output is correct
62 Correct 1758 ms 8736 KB Output is correct
63 Correct 1706 ms 8724 KB Output is correct
64 Correct 1978 ms 9436 KB Output is correct
65 Correct 1486 ms 8436 KB Output is correct
66 Correct 1149 ms 6340 KB Output is correct
67 Correct 1366 ms 6348 KB Output is correct
68 Correct 1324 ms 6344 KB Output is correct
69 Correct 1165 ms 6352 KB Output is correct
70 Correct 1349 ms 6352 KB Output is correct
71 Correct 1341 ms 6348 KB Output is correct
72 Correct 1371 ms 6356 KB Output is correct
73 Correct 1235 ms 6344 KB Output is correct
74 Correct 1254 ms 6344 KB Output is correct
75 Correct 1247 ms 6352 KB Output is correct
76 Correct 1123 ms 6264 KB Output is correct
77 Correct 1129 ms 6348 KB Output is correct
78 Correct 1122 ms 6348 KB Output is correct
79 Correct 1027 ms 6344 KB Output is correct
80 Correct 1046 ms 6356 KB Output is correct
81 Correct 1035 ms 6344 KB Output is correct
82 Correct 996 ms 6284 KB Output is correct
83 Correct 1006 ms 6352 KB Output is correct
84 Correct 990 ms 6416 KB Output is correct
85 Correct 2421 ms 9412 KB Output is correct
86 Correct 307 ms 6736 KB Output is correct
87 Correct 175 ms 6732 KB Output is correct
88 Correct 1895 ms 9436 KB Output is correct
89 Correct 2401 ms 9376 KB Output is correct
90 Correct 1766 ms 9500 KB Output is correct
91 Correct 1261 ms 6284 KB Output is correct
92 Correct 1234 ms 6344 KB Output is correct
93 Correct 1431 ms 6344 KB Output is correct
94 Correct 1837 ms 7928 KB Output is correct
95 Correct 1745 ms 7876 KB Output is correct
96 Correct 1866 ms 7880 KB Output is correct
97 Correct 1634 ms 9644 KB Output is correct
98 Correct 1792 ms 9400 KB Output is correct
99 Correct 2397 ms 9432 KB Output is correct
100 Correct 2510 ms 9344 KB Output is correct
101 Correct 2503 ms 9428 KB Output is correct
102 Correct 2518 ms 9424 KB Output is correct
103 Correct 2039 ms 8596 KB Output is correct
104 Correct 2078 ms 8596 KB Output is correct
105 Correct 1930 ms 8388 KB Output is correct
106 Correct 1715 ms 7852 KB Output is correct
107 Correct 1794 ms 8600 KB Output is correct
108 Correct 2362 ms 9188 KB Output is correct
109 Correct 1736 ms 8220 KB Output is correct