oj.uz

Submission #317466

# Submission time Handle Problem Language Result Execution time Memory
317466 2020-10-29T18:19:31 Z mohamedsobhi777 Parachute rings (IOI12_rings) C++14
37 / 100
 1927 ms 104280 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);

        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;

        for (int j = 0; j < N; ++j)
        {
                ++c;
                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()];
        }
        int ans1 = 0;
        if (th.size() == 1)
        {
                if (asy)
                        return 1 + (int)adj[*th.begin()].size();
                ++c;
                set<int> anss;
                int a = (*th.begin());
                if (check(a))
                {
                        anss.insert(a);
                }
                for (auto u : adj[a])
                {
                        ++c;
                        if (check(u))
                                anss.insert(u);
                }
                ans1 = (int)anss.size();
                //                return (int)anss.size();
        }
        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;
        }
        set<int> ass;
        if (th.size() == 0)
                return N;
        else
        {
                for (auto u : adj[*th.begin()])
                        ass.insert(u);
                ass.insert(*th.begin());
        }
        assert(th.size() == 1);
        for (auto i : ass)
        {
                ++c;
                if (check(i))
                {
                        if (th.size())
                                assert(ass.find(i) != ass.end());
                        ++ret;
                }
        }
        if (th.size())
        {
                assert(ret == ans1);
        }
        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 17 ms 27776 KB Output is correct
2 Correct 19 ms 27904 KB Output is correct
3 Correct 19 ms 27904 KB Output is correct
4 Correct 18 ms 27776 KB Output is correct
5 Correct 20 ms 28032 KB Output is correct
6 Correct 21 ms 28288 KB Output is correct
7 Correct 17 ms 27776 KB Output is correct
8 Correct 19 ms 27904 KB Output is correct
9 Correct 19 ms 27904 KB Output is correct
10 Correct 20 ms 27904 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 495 ms 46264 KB Output is correct
2 Correct 962 ms 55944 KB Output is correct
3 Correct 1927 ms 79680 KB Output is correct
4 Correct 1225 ms 65996 KB Output is correct
5 Correct 1226 ms 72348 KB Output is correct
6 Correct 1343 ms 104280 KB Output is correct
7 Correct 1794 ms 80480 KB Output is correct
8 Correct 1126 ms 60832 KB Output is correct
9 Correct 1218 ms 63096 KB Output is correct
10 Correct 792 ms 65272 KB Output is correct

Subtask #3
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 19 ms 27904 KB Output is correct
3 Correct 19 ms 27904 KB Output is correct
4 Correct 18 ms 27776 KB Output is correct
5 Correct 20 ms 28032 KB Output is correct
6 Correct 21 ms 28288 KB Output is correct
7 Correct 17 ms 27776 KB Output is correct
8 Correct 19 ms 27904 KB Output is correct
9 Correct 19 ms 27904 KB Output is correct
10 Correct 20 ms 27904 KB Output is correct
11 Incorrect 185 ms 28024 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 19 ms 27904 KB Output is correct
3 Correct 19 ms 27904 KB Output is correct
4 Correct 18 ms 27776 KB Output is correct
5 Correct 20 ms 28032 KB Output is correct
6 Correct 21 ms 28288 KB Output is correct
7 Correct 17 ms 27776 KB Output is correct
8 Correct 19 ms 27904 KB Output is correct
9 Correct 19 ms 27904 KB Output is correct
10 Correct 20 ms 27904 KB Output is correct
11 Incorrect 185 ms 28024 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 19 ms 27904 KB Output is correct
3 Correct 19 ms 27904 KB Output is correct
4 Correct 18 ms 27776 KB Output is correct
5 Correct 20 ms 28032 KB Output is correct
6 Correct 21 ms 28288 KB Output is correct
7 Correct 17 ms 27776 KB Output is correct
8 Correct 19 ms 27904 KB Output is correct
9 Correct 19 ms 27904 KB Output is correct
10 Correct 20 ms 27904 KB Output is correct
11 Correct 495 ms 46264 KB Output is correct
12 Correct 962 ms 55944 KB Output is correct
13 Correct 1927 ms 79680 KB Output is correct
14 Correct 1225 ms 65996 KB Output is correct
15 Correct 1226 ms 72348 KB Output is correct
16 Correct 1343 ms 104280 KB Output is correct
17 Correct 1794 ms 80480 KB Output is correct
18 Correct 1126 ms 60832 KB Output is correct
19 Correct 1218 ms 63096 KB Output is correct
20 Correct 792 ms 65272 KB Output is correct
21 Incorrect 185 ms 28024 KB Output isn't correct
22 Halted 0 ms 0 KB -