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Submission #317451

# Submission time Handle Problem Language Result Execution time Memory
317451 2020-10-29T18:02:08 Z mohamedsobhi777 Parachute rings (IOI12_rings) C++14
37 / 100
 1857 ms 104108 KB 
#include <bits/stdc++.h>

using namespace std;
int N;
const int cn = 1e6;

vector<int> adj[cn];
int deg[cn];
int vis[cn];
int c;
bool bd = 1;
int del;
vector<int> vec;
set<int> th;
int asy = 1;
int cs = 0;

struct dsu
{
        int fat[cn];
        dsu()
        {
                memset(fat, 0, sizeof fat);
                for (int i = 0; i < cn; ++i)
                        fat[i] = i;
        }
        inline int find(int x) { return fat[x] = (x == fat[x] ? x : find(fat[x])); }
        inline bool same(int x, int y) { return find(x) == find(y); }
        void link(int u, int v)
        {
                u = find(u);
                v = find(v);
                if (fat[u] != v)
                        fat[u] = v;
        }
} d1;

void dfs(int x, int p)
{
        vis[x] = c;
        int ch = (p != x);
        vec.push_back(x);
        for (auto u : adj[x])
        {
                if (u == p || del == u)
                        continue;
                if (vis[u] == c)
                        bd = 0;
                else
                        dfs(u, x), ++ch;
        }
        if (ch > 2)
                bd = 0;
}
set<int> bigs;

bool check(int i)
{
        del = i;
        for (auto u : adj[i])
        {
                deg[u]--;
                deg[i]--;
        }
        bool ok = 1;
        vec.clear();
        for (int j = 0; j < N; ++j)
        {
                if (vis[j] != c && i != j)
                {
                        bd = 1;
                        dfs(j, j);
                        ok &= bd;
                }
        }

        for (auto u : adj[i])
        {
                deg[u]++;
                deg[i]++;
        }
        return ok;
}

vector<int> cyc;
vector<int> now;
int onc[cn];

void detect(int x, int p)
{
        if (vis[x] == c)
        {
                cyc = now;
                for (auto u : now)
                        onc[u] = 1;
                return;
        }
        now.push_back(x);

        vis[x] = c;
        for (auto u : adj[x])
        {
                if (u == p || (int)cyc.size())
                        continue;
                detect(u, x);
        }
        now.pop_back();
}

int brute()
{
        int ret = 0;
        set<int> uni;

        if (cs > 1 || bigs.size() > 1 || th.size() > 2)
                return 0;
        if (th.size() == 0 && asy)
                return N;
        if (cs == 1 && th.size() == 0)
                return (int)cyc.size();
        if (bigs.size())
        {
                if (asy)
                        return 1;
                return onc[*bigs.begin()];
        }

        if (th.size() == 1)
        {
                if (asy)
                        return 1 + (int)adj[*th.begin()].size();
                ++c;
                int tret = check(*th.begin());
                for (auto u : adj[*th.begin()])
                {
                        ++c;
                        tret += check(u);
                }
                return tret;
        }
        else if (th.size() == 2)
        {

                int a = *th.begin();
                int b = *th.rbegin();
                if (cs)
                {
                        if (onc[a] + onc[b] == 0)
                                return 0;
                }
                map<int, int> mp;
                for (auto u : adj[a])
                        mp[u]++;
                for (auto u : adj[b])
                        mp[u]++;
                mp[a]++;
                mp[b]++;
                for (auto u : mp)
                {
                        if ((onc[u.first] || !cs) && u.second == 2)
                                ++ret;
                }
                return ret;
        }

        if (th.size() == 0)
                return N;

        for (int i = 0; i < N; ++i)
        {
                ++c;
                if (check(i))
                        ++ret;
        }

        return ret;
}

void Init(int N_)
{

        N = N_;
}
void Link(int A, int B)
{
        adj[A].push_back(B);
        adj[B].push_back(A);
        cs += (d1.same(A, B));
        if (d1.same(A, B) && asy)
        {
                ++c;
                detect(A, A);
                asy = 0;
        }

        d1.link(A, B);
        deg[A]++;
        deg[B]++;
        if (deg[A] > 3)
                bigs.insert(A);
        if (deg[B] > 3)
                bigs.insert(B);
        if (deg[A] == 3)
        {
                th.insert(A);
        }
        if (deg[B] == 3)
        {
                th.insert(B);
        }
}

int CountCritical()
{
        if (bigs.size() > 1)
                return 0;
        return brute();
        return N;
}

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 27776 KB Output is correct
2 Correct 21 ms 27904 KB Output is correct
3 Correct 21 ms 27904 KB Output is correct
4 Correct 19 ms 27776 KB Output is correct
5 Correct 21 ms 28032 KB Output is correct
6 Correct 22 ms 28288 KB Output is correct
7 Correct 19 ms 27776 KB Output is correct
8 Correct 20 ms 27904 KB Output is correct
9 Correct 21 ms 27904 KB Output is correct
10 Correct 21 ms 27904 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 473 ms 46200 KB Output is correct
2 Correct 928 ms 55996 KB Output is correct
3 Correct 1857 ms 79608 KB Output is correct
4 Correct 1190 ms 66040 KB Output is correct
5 Correct 1205 ms 72292 KB Output is correct
6 Correct 1302 ms 104108 KB Output is correct
7 Correct 1729 ms 80404 KB Output is correct
8 Correct 1106 ms 60792 KB Output is correct
9 Correct 1180 ms 63040 KB Output is correct
10 Correct 789 ms 65400 KB Output is correct

Subtask #3
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 27776 KB Output is correct
2 Correct 21 ms 27904 KB Output is correct
3 Correct 21 ms 27904 KB Output is correct
4 Correct 19 ms 27776 KB Output is correct
5 Correct 21 ms 28032 KB Output is correct
6 Correct 22 ms 28288 KB Output is correct
7 Correct 19 ms 27776 KB Output is correct
8 Correct 20 ms 27904 KB Output is correct
9 Correct 21 ms 27904 KB Output is correct
10 Correct 21 ms 27904 KB Output is correct
11 Incorrect 25 ms 28032 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 27776 KB Output is correct
2 Correct 21 ms 27904 KB Output is correct
3 Correct 21 ms 27904 KB Output is correct
4 Correct 19 ms 27776 KB Output is correct
5 Correct 21 ms 28032 KB Output is correct
6 Correct 22 ms 28288 KB Output is correct
7 Correct 19 ms 27776 KB Output is correct
8 Correct 20 ms 27904 KB Output is correct
9 Correct 21 ms 27904 KB Output is correct
10 Correct 21 ms 27904 KB Output is correct
11 Incorrect 25 ms 28032 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 27776 KB Output is correct
2 Correct 21 ms 27904 KB Output is correct
3 Correct 21 ms 27904 KB Output is correct
4 Correct 19 ms 27776 KB Output is correct
5 Correct 21 ms 28032 KB Output is correct
6 Correct 22 ms 28288 KB Output is correct
7 Correct 19 ms 27776 KB Output is correct
8 Correct 20 ms 27904 KB Output is correct
9 Correct 21 ms 27904 KB Output is correct
10 Correct 21 ms 27904 KB Output is correct
11 Correct 473 ms 46200 KB Output is correct
12 Correct 928 ms 55996 KB Output is correct
13 Correct 1857 ms 79608 KB Output is correct
14 Correct 1190 ms 66040 KB Output is correct
15 Correct 1205 ms 72292 KB Output is correct
16 Correct 1302 ms 104108 KB Output is correct
17 Correct 1729 ms 80404 KB Output is correct
18 Correct 1106 ms 60792 KB Output is correct
19 Correct 1180 ms 63040 KB Output is correct
20 Correct 789 ms 65400 KB Output is correct
21 Incorrect 25 ms 28032 KB Output isn't correct
22 Halted 0 ms 0 KB -