oj.uz

Submission #767092

# Submission time Handle Problem Language Result Execution time Memory
767092 2023-06-26T11:32:55 Z boris_mihov Parachute rings (IOI12_rings) C++17
100 / 100
 1481 ms 82212 KB 
#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <vector>
#include <set>
 
typedef long long llong;
const int MAXN = 1000000 + 10;
const int INF  = 1e9;
 
int n;
int d[MAXN];
int d2[MAXN];
struct DSU
{
    int par[MAXN];
    int dep[MAXN];
    int sz[MAXN];
 
    void build()
    {
        for (int i = 1 ; i <= n ; ++i)
        {
            par[i] = i;
            dep[i] = 1;
            sz[i] = 1;
        }
    }
 
    int find(int u)
    {
        if (u == par[u]) return u;
        return par[u] = find(par[u]);
    }
 
    void connect(int u, int v)
    {
        u = find(u);
        v = find(v);
 
        if (u == v)
        {
            assert(false);
            return;
        }
 
        if (dep[u] < dep[v])
        {
            std::swap(u, v);
        }
 
        if (dep[u] == dep[v])
        {
            dep[v]++;
        }
 
        par[u] = v;
        sz[v] += sz[u];
    }
 
    bool areConnected(int u, int v)
    {
        return find(u) == find(v);
    }
};
 
DSU dsu;
DSU dsu2;
int ans;
void Init(int N_) 
{
    n = N_;
    ans = n;
    dsu.build();
}
 
int cycle;
bool isBad;
int cntThree;
int theNode = -1;
std::set <int> toNode;
std::set <int> toNode2;
std::vector <int> three;
std::vector <std::pair <int,int>> added;
std::vector <int> g[MAXN];
 
void reConnect(int node)
{
    dsu.build();
    theNode = node;
    std::fill(d + 1, d + 1 + n, 0);
    for (const auto &[u, v] : added)
    {
        d[u]++;
        d[v]++;
        if (u == node)
        {
            toNode.insert(v);
            continue;
        }
 
        if (v == node)
        {
            toNode.insert(u);
            continue;
        }
 
        if (dsu.areConnected(u, v))
        {
            isBad = true;
            return;
        }
 
        dsu.connect(u, v);
    }
 
    for (int i = 1 ; i <= n ; ++i)
    {
        if (d[i] - toNode.count(i) > 2 && i != node)
        {
            isBad = true;
            return;
        }
    }
}
 
bool check(int node)
{
    dsu2.build();
    std::fill(d2 + 1, d2 + 1 + n, 0);
    for (const auto &[u, v] : added)
    {
        d2[u]++;
        d2[v]++;
        if (u == node)
        {
            d2[v]--;
            continue;
        }
 
        if (v == node)
        {
            d2[u]--;
            continue;
        }
 
        if (dsu2.areConnected(u, v))
        {
            return false;
        }
 
        dsu2.connect(u, v);
    }
 
    for (int i = 1 ; i <= n ; ++i)
    {
        if (d2[i] > 2 && i != node)
        {
            return false;
        }
    }
 
    return true;
}
 
bool isLenThree = false;
void Link(int u, int v)
{
    u++;
    v++;
    if (isBad)
    {
        return;
    }
 
    added.push_back({u, v});
    if (theNode != -1)
    {
        if (v == theNode)
        {
            std::swap(u, v);
        }
 
        if (u == theNode)
        {
            d[v]++;
            toNode.insert(v);
            if (d[v] > 3)
            {
                isBad = true;
                return;
            }
        } else
        {
            d[v]++;
            d[u]++;
            if (d[v] - toNode.count(v) > 2)
            {
                isBad = true;
                return;
            }
 
            if (d[u] - toNode.count(u) > 2)
            {
                isBad = true;
                return;
            }
 
            if (dsu.areConnected(u, v))
            {
                isBad = true;
                return;
            }
 
            dsu.connect(u, v);
        }
    } else
    {
        d[u]++;
        d[v]++;
        if (d[u] == 4 && d[v] == 4)
        {
            isBad = true;
            return;
        }
 
        if (d[u] == 4)
        {
            reConnect(u);
            return;
        }
 
        if (d[v] == 4)
        {
            reConnect(v);
            return;
        }
 
        cntThree += (d[u] == 3);
        cntThree += (d[v] == 3);
 
        g[u].push_back(v);
        g[v].push_back(u);
 
        if (d[u] == 3)
        {
            three.push_back(u);
        }
 
        if (d[v] == 3)
        {
            three.push_back(v);
        }
 
        if (cntThree > 4)
        {
            isBad = true;
            return;
        }
 
        if (cycle && dsu.areConnected(u, v))
        {
            if (dsu.find(u) != dsu.find(cycle))
            {
                isBad = true;
                return;
            }
        }
 
        if (!cycle && dsu.areConnected(u, v))
        {
            for (const int &x : g[u])
            {
                if (x == v)
                {
                    isLenThree = true;
                }
            }
            
            cycle = u;
        }
 
        if (!dsu.areConnected(u, v))
        {
            dsu.connect(u, v);
        }

        if (cntThree != 0 && cycle != 0)
        {
            std::set <int> good123;
            if (cntThree <= 2)
            {
                for (const int &u : three)
                {
                    good123.insert(u);
                    for (const int &i : g[u])
                        good123.insert(i);
                }
            } else
            {
                for (const int &u : three)
                {
                    good123.insert(u);
                }
            }
 
            ans = 0;
            for (const int &u : good123)
            {
                ans += check(u);
            }
 
            return;
        }
 
        if (cycle)
        {   
            ans = dsu.sz[dsu.find(cycle)];
            return;
        }
 
        if (cntThree > 4)
        {
            isBad = true;
            return;
        }
 
        if (cntThree == 0)
        {
            ans = n;
            return;
        }
 
        if (cntThree == 1)
        {
            ans = 4;
            return;
        }
 
        ans = 0;
        for (const int &i : three)
        {
            int curr = 0;
            for (const int &u : g[i])
            {
                curr += (d[u] == 3);
            }
 
            if (curr == cntThree - 1)
            {
                ans++;
            }
        }
 
        if (cntThree == 2)
        {
            for (const int &u : g[three[0]])
            {
                for (const int &v : g[three[1]])
                {
                    if (u == v)
                    {
                        ans++;
                    }
                }
            }
        }
    }
}
 
int CountCritical() 
{
    if (isBad) return 0;
    if (theNode != -1) return 1;
    return ans;
}
 
/*
6 14
1 2
-1
1 3
-1
2 3
-1
1 0
-1
3 4
-1
2 5
-1
5 4
-1
*/

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 23764 KB Output is correct
2 Correct 11 ms 24016 KB Output is correct
3 Correct 11 ms 24064 KB Output is correct
4 Correct 11 ms 23764 KB Output is correct
5 Correct 10 ms 24020 KB Output is correct
6 Correct 12 ms 24148 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 11 ms 24020 KB Output is correct
9 Correct 12 ms 24148 KB Output is correct
10 Correct 16 ms 24092 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 276 ms 52324 KB Output is correct
2 Correct 404 ms 59668 KB Output is correct
3 Correct 178 ms 40316 KB Output is correct
4 Correct 883 ms 78432 KB Output is correct
5 Correct 913 ms 78536 KB Output is correct
6 Correct 833 ms 77204 KB Output is correct
7 Correct 166 ms 40244 KB Output is correct
8 Correct 792 ms 74932 KB Output is correct
9 Correct 866 ms 78408 KB Output is correct
10 Correct 595 ms 76324 KB Output is correct

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 23764 KB Output is correct
2 Correct 11 ms 24016 KB Output is correct
3 Correct 11 ms 24064 KB Output is correct
4 Correct 11 ms 23764 KB Output is correct
5 Correct 10 ms 24020 KB Output is correct
6 Correct 12 ms 24148 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 11 ms 24020 KB Output is correct
9 Correct 12 ms 24148 KB Output is correct
10 Correct 16 ms 24092 KB Output is correct
11 Correct 195 ms 24212 KB Output is correct
12 Correct 235 ms 24756 KB Output is correct
13 Correct 185 ms 24620 KB Output is correct
14 Correct 12 ms 24148 KB Output is correct
15 Correct 15 ms 24388 KB Output is correct
16 Correct 13 ms 24404 KB Output is correct
17 Correct 15 ms 24148 KB Output is correct
18 Correct 12 ms 24148 KB Output is correct
19 Correct 13 ms 24404 KB Output is correct
20 Correct 13 ms 24404 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 23764 KB Output is correct
2 Correct 11 ms 24016 KB Output is correct
3 Correct 11 ms 24064 KB Output is correct
4 Correct 11 ms 23764 KB Output is correct
5 Correct 10 ms 24020 KB Output is correct
6 Correct 12 ms 24148 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 11 ms 24020 KB Output is correct
9 Correct 12 ms 24148 KB Output is correct
10 Correct 16 ms 24092 KB Output is correct
11 Correct 195 ms 24212 KB Output is correct
12 Correct 235 ms 24756 KB Output is correct
13 Correct 185 ms 24620 KB Output is correct
14 Correct 12 ms 24148 KB Output is correct
15 Correct 15 ms 24388 KB Output is correct
16 Correct 13 ms 24404 KB Output is correct
17 Correct 15 ms 24148 KB Output is correct
18 Correct 12 ms 24148 KB Output is correct
19 Correct 13 ms 24404 KB Output is correct
20 Correct 13 ms 24404 KB Output is correct
21 Correct 23 ms 25788 KB Output is correct
22 Correct 31 ms 26928 KB Output is correct
23 Correct 37 ms 27832 KB Output is correct
24 Correct 40 ms 26372 KB Output is correct
25 Correct 19 ms 25744 KB Output is correct
26 Correct 32 ms 26072 KB Output is correct
27 Correct 38 ms 28400 KB Output is correct
28 Correct 47 ms 26772 KB Output is correct
29 Correct 27 ms 25852 KB Output is correct
30 Correct 56 ms 29220 KB Output is correct

Subtask #5
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 23764 KB Output is correct
2 Correct 11 ms 24016 KB Output is correct
3 Correct 11 ms 24064 KB Output is correct
4 Correct 11 ms 23764 KB Output is correct
5 Correct 10 ms 24020 KB Output is correct
6 Correct 12 ms 24148 KB Output is correct
7 Correct 12 ms 23892 KB Output is correct
8 Correct 11 ms 24020 KB Output is correct
9 Correct 12 ms 24148 KB Output is correct
10 Correct 16 ms 24092 KB Output is correct
11 Correct 276 ms 52324 KB Output is correct
12 Correct 404 ms 59668 KB Output is correct
13 Correct 178 ms 40316 KB Output is correct
14 Correct 883 ms 78432 KB Output is correct
15 Correct 913 ms 78536 KB Output is correct
16 Correct 833 ms 77204 KB Output is correct
17 Correct 166 ms 40244 KB Output is correct
18 Correct 792 ms 74932 KB Output is correct
19 Correct 866 ms 78408 KB Output is correct
20 Correct 595 ms 76324 KB Output is correct
21 Correct 195 ms 24212 KB Output is correct
22 Correct 235 ms 24756 KB Output is correct
23 Correct 185 ms 24620 KB Output is correct
24 Correct 12 ms 24148 KB Output is correct
25 Correct 15 ms 24388 KB Output is correct
26 Correct 13 ms 24404 KB Output is correct
27 Correct 15 ms 24148 KB Output is correct
28 Correct 12 ms 24148 KB Output is correct
29 Correct 13 ms 24404 KB Output is correct
30 Correct 13 ms 24404 KB Output is correct
31 Correct 23 ms 25788 KB Output is correct
32 Correct 31 ms 26928 KB Output is correct
33 Correct 37 ms 27832 KB Output is correct
34 Correct 40 ms 26372 KB Output is correct
35 Correct 19 ms 25744 KB Output is correct
36 Correct 32 ms 26072 KB Output is correct
37 Correct 38 ms 28400 KB Output is correct
38 Correct 47 ms 26772 KB Output is correct
39 Correct 27 ms 25852 KB Output is correct
40 Correct 56 ms 29220 KB Output is correct
41 Correct 159 ms 41804 KB Output is correct
42 Correct 329 ms 56184 KB Output is correct
43 Correct 192 ms 40804 KB Output is correct
44 Correct 422 ms 53068 KB Output is correct
45 Correct 571 ms 61412 KB Output is correct
46 Correct 540 ms 80376 KB Output is correct
47 Correct 718 ms 82212 KB Output is correct
48 Correct 216 ms 48268 KB Output is correct
49 Correct 578 ms 80904 KB Output is correct
50 Correct 601 ms 80404 KB Output is correct
51 Correct 191 ms 42512 KB Output is correct
52 Correct 1481 ms 58076 KB Output is correct
53 Correct 155 ms 47692 KB Output is correct
54 Correct 762 ms 79796 KB Output is correct
55 Correct 364 ms 57208 KB Output is correct