Submission #551279

# Submission time Handle Problem Language Result Execution time Memory
551279 2022-04-20T08:11:23 Z elazarkoren Parachute rings (IOI12_rings) C++17
52 / 100
4000 ms 224508 KB
#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vii;

const int MAX_N = 1e6 + 5;

struct Dsu {
    vi par, sz, deg;
    vector<set<pii, greater<pii>>> degs;
    set<int> bad_comps;
    int erased_node;
    bool good = true;
    Dsu() {}
    Dsu(int n, int node): erased_node(node) {
        par.resize(n), sz.resize(n), deg.resize(n);
        degs.resize(n);
        for (int i = 0; i < n; i++) {
            par[i] = i, sz[i] = 1;
            degs[i].insert({0, i});
        }
    }
    int Find(int i) {
        return par[i] == i ? i : par[i] = Find(par[i]);
    }
    void Union(int a, int b) {
        int pa = Find(a), pb = Find(b);
        if (pa == pb) {
            bad_comps.insert(pa);
            good = false;
            return;
        }
        if (sz[pa] < sz[pb]) swap(pa, pb);
        if (bad_comps.count(pb)) {
            bad_comps.erase(bad_comps.find(pb));
            bad_comps.insert(pa);
            good = false;
        }
        sz[pa] += sz[pb];
        par[pb] = pa;
        for (pii p : degs[pb]) {
            degs[pa].insert(p);
        }
        degs[pb].clear();
    }
    void Add(int a, int b) {
        if (a == erased_node || b == erased_node) return;
        Union(a, b);
        int pa = Find(a);
        degs[pa].erase(degs[pa].find({deg[a], a}));
        degs[pa].erase(degs[pa].find({deg[b], b}));
        deg[a]++, deg[b]++;
        degs[pa].insert({deg[a], a});
        degs[pa].insert({deg[b], b});
        if (deg[a] > 2 || deg[b] > 2) {
            bad_comps.insert(pa);
            good = false;
        }
    }
};

int n;

Dsu d1;
bool changed = false;

vi graph[MAX_N];

void Init(int N_) {
    n = N_;
    d1 = Dsu(n, -1);
}

vector<Dsu> dsu;
vii edges;

void Link(int a, int b) {
    graph[a].push_back(b);
    graph[b].push_back(a);
    edges.push_back({a, b});
    if (!changed) {
        d1.Add(a, b);
    } else {
        for (auto &d : dsu) {
            d.Add(a, b);
        }
    }
}

int CountCritical() {
    if (changed) {
        int cnt = 0;
        for (auto &d : dsu) cnt += d.good;
        return cnt;
    }
    if (d1.good) return n;
    if (d1.bad_comps.size() == 1) {
        int node = *d1.bad_comps.begin();
        auto [max_deg, v] = *d1.degs[node].begin();
        if (max_deg == 2) return d1.sz[node];
        changed = true;
        int cnt = 0;
        dsu.push_back(Dsu(n, v));
        if (max_deg <= 3) {
            for (int neighbor : graph[v]) {
                dsu.push_back(Dsu(n, neighbor));
            }
        }
        for (auto &d : dsu) {
            for (pii p : edges) {
                d.Add(p.x, p.y);
            }
        }
        return CountCritical();
    }
    changed = true;
    return 0;
}

Compilation message

rings.cpp: In function 'int CountCritical()':
rings.cpp:110:13: warning: unused variable 'cnt' [-Wunused-variable]
  110 |         int cnt = 0;
      |             ^~~
# Verdict Execution time Memory Grader output
1 Correct 16 ms 23764 KB Output is correct
2 Correct 20 ms 24888 KB Output is correct
3 Correct 26 ms 25044 KB Output is correct
4 Correct 14 ms 23892 KB Output is correct
5 Correct 21 ms 24196 KB Output is correct
6 Correct 23 ms 24660 KB Output is correct
7 Correct 16 ms 24276 KB Output is correct
8 Correct 17 ms 24332 KB Output is correct
9 Correct 33 ms 26656 KB Output is correct
10 Correct 33 ms 26724 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1461 ms 99352 KB Output is correct
2 Execution timed out 4074 ms 224508 KB Time limit exceeded
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 16 ms 23764 KB Output is correct
2 Correct 20 ms 24888 KB Output is correct
3 Correct 26 ms 25044 KB Output is correct
4 Correct 14 ms 23892 KB Output is correct
5 Correct 21 ms 24196 KB Output is correct
6 Correct 23 ms 24660 KB Output is correct
7 Correct 16 ms 24276 KB Output is correct
8 Correct 17 ms 24332 KB Output is correct
9 Correct 33 ms 26656 KB Output is correct
10 Correct 33 ms 26724 KB Output is correct
11 Correct 36 ms 26744 KB Output is correct
12 Correct 56 ms 29672 KB Output is correct
13 Correct 55 ms 29644 KB Output is correct
14 Correct 21 ms 26268 KB Output is correct
15 Correct 27 ms 28336 KB Output is correct
16 Correct 24 ms 25328 KB Output is correct
17 Correct 22 ms 25296 KB Output is correct
18 Correct 20 ms 26460 KB Output is correct
19 Correct 24 ms 25424 KB Output is correct
20 Correct 48 ms 29592 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 16 ms 23764 KB Output is correct
2 Correct 20 ms 24888 KB Output is correct
3 Correct 26 ms 25044 KB Output is correct
4 Correct 14 ms 23892 KB Output is correct
5 Correct 21 ms 24196 KB Output is correct
6 Correct 23 ms 24660 KB Output is correct
7 Correct 16 ms 24276 KB Output is correct
8 Correct 17 ms 24332 KB Output is correct
9 Correct 33 ms 26656 KB Output is correct
10 Correct 33 ms 26724 KB Output is correct
11 Correct 36 ms 26744 KB Output is correct
12 Correct 56 ms 29672 KB Output is correct
13 Correct 55 ms 29644 KB Output is correct
14 Correct 21 ms 26268 KB Output is correct
15 Correct 27 ms 28336 KB Output is correct
16 Correct 24 ms 25328 KB Output is correct
17 Correct 22 ms 25296 KB Output is correct
18 Correct 20 ms 26460 KB Output is correct
19 Correct 24 ms 25424 KB Output is correct
20 Correct 48 ms 29592 KB Output is correct
21 Correct 52 ms 30592 KB Output is correct
22 Correct 84 ms 34448 KB Output is correct
23 Correct 105 ms 37152 KB Output is correct
24 Correct 125 ms 45612 KB Output is correct
25 Correct 105 ms 76832 KB Output is correct
26 Correct 447 ms 76860 KB Output is correct
27 Correct 124 ms 36300 KB Output is correct
28 Correct 681 ms 74364 KB Output is correct
29 Correct 211 ms 79148 KB Output is correct
30 Correct 212 ms 38612 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 16 ms 23764 KB Output is correct
2 Correct 20 ms 24888 KB Output is correct
3 Correct 26 ms 25044 KB Output is correct
4 Correct 14 ms 23892 KB Output is correct
5 Correct 21 ms 24196 KB Output is correct
6 Correct 23 ms 24660 KB Output is correct
7 Correct 16 ms 24276 KB Output is correct
8 Correct 17 ms 24332 KB Output is correct
9 Correct 33 ms 26656 KB Output is correct
10 Correct 33 ms 26724 KB Output is correct
11 Correct 1461 ms 99352 KB Output is correct
12 Execution timed out 4074 ms 224508 KB Time limit exceeded
13 Halted 0 ms 0 KB -