oj.uz

답안 #317483

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
317483 2020-10-29T18:48:12 Z mohamedsobhi777 낙하산 고리들 (IOI12_rings) C++14
0 / 100
 969 ms 55928 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;
vector<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;
}
vector<int> bigs;
vector<int> cyc;
vector<int> now;
int onc[cn];

bool check(int i)
{
        del = i;
        for (auto u : adj[i])
        {
                deg[u]--;
                deg[i]--;
        }
        bool ok = 1;
        ++c;
        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;
}

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 4;
        }
        int ans1 = 0;
        if (th.size() == 1)
        {
                //if (asy)
                //      return 1 + (int)adj[*th.begin()].size();
                ++c;
                int a = *th.begin();
                if (cs == 1)
                {
                        ans1 = onc[a];
                        for (auto u : adj[a])
                                ans1 += onc[u];
                        return ans1;
                }

                //                return (int)anss.size();
        }
        else if (th.size() == 2)
        {

                int a = th[0];
                int b = th[1];
                if (cs)
                {
                        if (onc[a] + onc[b] == 0)
                                return 0;
                }
                unordered_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;

        ret = 0;
        for (int i = 0; i < N; ++i)
        {
                ret += check(i);
        }
        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.push_back(A);
        if (deg[B] > 3)
                bigs.push_back(B);
        if (deg[A] == 3)
        {
                th.push_back(A);
        }
        if (deg[B] == 3)
        {
                th.push_back(B);
        }
}

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

Subtask #1
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 20 ms 27904 KB Output is correct
3 Incorrect 20 ms 27904 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 17.0

# 결과 실행 시간 메모리 Grader output
1 Correct 478 ms 46200 KB Output is correct
2 Incorrect 969 ms 55928 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 18.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 20 ms 27904 KB Output is correct
3 Incorrect 20 ms 27904 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 20 ms 27904 KB Output is correct
3 Incorrect 20 ms 27904 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 27776 KB Output is correct
2 Correct 20 ms 27904 KB Output is correct
3 Incorrect 20 ms 27904 KB Output isn't correct
4 Halted 0 ms 0 KB -