oj.uz

Submission #1041083

# Submission time Handle Problem Language Result Execution time Memory
1041083 2024-08-01T15:12:44 Z jer033 Parachute rings (IOI12_rings) C++17
37 / 100
 4000 ms 244836 KB 
#include <bits/stdc++.h>
using namespace std;

int N;
int curr_answer;
bool second_stage;

class LinkedIn{
public:
    vector<vector<int>> edges;
    vector<int> chains;
    //value encoded: other endpoint of chain (itself if 0 connections), or -1 if it has 2 connections
    vector<int> degree;
    int id;
    int cycle_count;
    int cycle_size;
    bool three_exists;

    LinkedIn(int N_, int k)
    {
        edges = vector<vector<int>> (N_);
        chains = vector<int> (N_);
        for (int i=0; i<N_; i++)
            chains[i] = i;
        degree = vector<int> (N_, 0);
        
        cycle_count = 0;
        cycle_size = 0;
        three_exists = 0;
        id = k;
    };

    int CreateLink(int A, int B)
    {
        degree[A]++;
        degree[B]++;
        
        if ((chains[A]>=0) and (chains[B]>=0))
        {
            if ((chains[A]==B) and (chains[B]==A))
            {
                cycle_count++;
                cycle_count = min(cycle_count, 2);
                if (cycle_count == 1)
                {
                    vector<int> visited(N, 0);
                    visited[A] = 1;
                    int curr = A;
                    cycle_size = 1;
                    while (curr!=B)
                    {
                        int next_node;
                        for (int c: edges[curr])
                            if (visited[c]==0)
                                next_node = c;
                        visited[next_node] = 1;
                        curr = next_node;
                        cycle_size++;
                    }
                    //cout << "A cycle of size " << cycle_size << " has been formed\n";
                }
                chains[A] = -1;
                chains[B] = -1;
            }
            else
            {
                int newchainsA, newchainsB;
                int newchains2A, newchains2B;
                if (chains[A]==A)
                    newchainsA = chains[B];
                else
                {
                    newchains2A = chains[B];
                    newchainsA = -1;
                }
                if (chains[B]==B)
                    newchainsB = chains[A];
                else
                {
                    newchains2B = chains[A];
                    newchainsB = -1;
                }

                if (chains[A]==A)
                    chains[A] = newchainsA;
                else
                {
                    chains[chains[A]] = newchains2A;
                    chains[A] = newchainsA;
                }

                if (chains[B]==B)
                    chains[B] = newchainsB;
                else
                {
                    chains[chains[B]] = newchains2B;
                    chains[B] = newchainsB;
                }
            }
        }
        else{
            three_exists = 1;
        }

        if (id == 0)
        {
            edges[A].push_back(B);
            edges[B].push_back(A);
        }

        if (degree[A]>=3)
            three_exists = 1;
        if (degree[B]>=3)
            three_exists = 1;

        /*for (int i=0; i<N; i++)
            cout << chains[i] << ' ';
        cout << '\n';*/

        if (three_exists)
            return 3;
        else if (cycle_count > 0)
            return min(cycle_count, 2);
        return 0;
    };

    int answer()
    {
        if (cycle_count>=2)
            return 0;
        if (cycle_count==1)
            return cycle_size;
        return N;
    }

    int answer_2()
    {
        if (three_exists)
            return 0;
        if (cycle_count >= 1)
            return 0;
        return 1;
    }
};

int c1, c2, c3, c4;
LinkedIn sys_0(0, 0);
LinkedIn sys_1(0, 1);
LinkedIn sys_2(0, 2);
LinkedIn sys_3(0, 3);
LinkedIn sys_4(0, 4);

void Init(int N_) {
    N = N_;
    curr_answer = N_;
    sys_0 = LinkedIn(N_, 0);
    second_stage = 0;
}

void Link(int A, int B) {
    if (second_stage == 0)
    {
        int result = sys_0.CreateLink(A, B);
        if (result != 3)
        {
            curr_answer = sys_0.answer();
        }
        else
        {
            second_stage = 1;
            vector<vector<int>> con = sys_0.edges;
            vector<int> deg = sys_0.degree;
            int center;
            if (deg[A] == 3)
                center = A;
            else
                center = B;
            c1 = center;
            c2 = con[center][0];
            c3 = con[center][1];
            c4 = con[center][2];
            sys_1 = LinkedIn(N, 1);
            sys_2 = LinkedIn(N, 2);
            sys_3 = LinkedIn(N, 3);
            sys_4 = LinkedIn(N, 4);
            //cout << c1 << c2 << c3 << c4 << '\n';
            for (int i=0; i<N; i++)
                for (int j: con[i])
                    if (i<j)
                    {
                        if ((i!=c1) and (j!=c1))
                            int x = sys_1.CreateLink(i, j);
                        if ((i!=c2) and (j!=c2))
                            int x = sys_2.CreateLink(i, j);
                        if ((i!=c3) and (j!=c3))
                            int x = sys_3.CreateLink(i, j);
                        if ((i!=c4) and (j!=c4))
                            int x = sys_4.CreateLink(i, j);
                    }
            curr_answer = sys_1.answer_2() + sys_2.answer_2() + sys_3.answer_2() + sys_4.answer_2();
        }
    }
    else
    {
        int i = A;
        int j = B;
        if ((i!=c1) and (j!=c1))
            int x = sys_1.CreateLink(i, j);
        if ((i!=c2) and (j!=c2))
            int x = sys_2.CreateLink(i, j);
        if ((i!=c3) and (j!=c3))
            int x = sys_3.CreateLink(i, j);
        if ((i!=c4) and (j!=c4))
            int x = sys_4.CreateLink(i, j);
                    
        curr_answer = sys_1.answer_2() + sys_2.answer_2() + sys_3.answer_2() + sys_4.answer_2();
    }
}

int CountCritical() {
    return curr_answer;
}

/*int main()
{
    Init(1'000'000);
    for (int i=0; i<50'000; i++)
    {
        Link(i, i+1);
    }
    Link(76892, 291238);
    Link(4, 100);
    cout << CountCritical() << '\n';
}*/

Compilation message

rings.cpp: In function 'void Link(int, int)':
rings.cpp:192:33: warning: unused variable 'x' [-Wunused-variable]
  192 |                             int x = sys_1.CreateLink(i, j);
      |                                 ^
rings.cpp:194:33: warning: unused variable 'x' [-Wunused-variable]
  194 |                             int x = sys_2.CreateLink(i, j);
      |                                 ^
rings.cpp:196:33: warning: unused variable 'x' [-Wunused-variable]
  196 |                             int x = sys_3.CreateLink(i, j);
      |                                 ^
rings.cpp:198:33: warning: unused variable 'x' [-Wunused-variable]
  198 |                             int x = sys_4.CreateLink(i, j);
      |                                 ^
rings.cpp:208:17: warning: unused variable 'x' [-Wunused-variable]
  208 |             int x = sys_1.CreateLink(i, j);
      |                 ^
rings.cpp:210:17: warning: unused variable 'x' [-Wunused-variable]
  210 |             int x = sys_2.CreateLink(i, j);
      |                 ^
rings.cpp:212:17: warning: unused variable 'x' [-Wunused-variable]
  212 |             int x = sys_3.CreateLink(i, j);
      |                 ^
rings.cpp:214:17: warning: unused variable 'x' [-Wunused-variable]
  214 |             int x = sys_4.CreateLink(i, j);
      |                 ^
rings.cpp: In member function 'int LinkedIn::CreateLink(int, int)':
rings.cpp:96:39: warning: 'newchains2B' may be used uninitialized in this function [-Wmaybe-uninitialized]
   96 |                     chains[chains[B]] = newchains2B;
rings.cpp:56:42: warning: 'next_node' may be used uninitialized in this function [-Wmaybe-uninitialized]
   56 |                         visited[next_node] = 1;
      |                                          ^

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 1372 KB Output is correct
3 Correct 1 ms 1372 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 1 ms 1372 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 1372 KB Output is correct
10 Correct 2 ms 1372 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 129 ms 32892 KB Output is correct
2 Correct 377 ms 175444 KB Output is correct
3 Correct 331 ms 185172 KB Output is correct
4 Correct 439 ms 66824 KB Output is correct
5 Correct 441 ms 66888 KB Output is correct
6 Correct 546 ms 65656 KB Output is correct
7 Correct 364 ms 185312 KB Output is correct
8 Correct 552 ms 224852 KB Output is correct
9 Correct 642 ms 244836 KB Output is correct
10 Correct 295 ms 65108 KB Output is correct

Subtask #3
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 1372 KB Output is correct
3 Correct 1 ms 1372 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 1 ms 1372 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 1372 KB Output is correct
10 Correct 2 ms 1372 KB Output is correct
11 Execution timed out 4043 ms 1372 KB Time limit exceeded
12 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 1372 KB Output is correct
3 Correct 1 ms 1372 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 1 ms 1372 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 1372 KB Output is correct
10 Correct 2 ms 1372 KB Output is correct
11 Execution timed out 4043 ms 1372 KB Time limit exceeded
12 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 1372 KB Output is correct
3 Correct 1 ms 1372 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 1 ms 1372 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 2 ms 1372 KB Output is correct
10 Correct 2 ms 1372 KB Output is correct
11 Correct 129 ms 32892 KB Output is correct
12 Correct 377 ms 175444 KB Output is correct
13 Correct 331 ms 185172 KB Output is correct
14 Correct 439 ms 66824 KB Output is correct
15 Correct 441 ms 66888 KB Output is correct
16 Correct 546 ms 65656 KB Output is correct
17 Correct 364 ms 185312 KB Output is correct
18 Correct 552 ms 224852 KB Output is correct
19 Correct 642 ms 244836 KB Output is correct
20 Correct 295 ms 65108 KB Output is correct
21 Execution timed out 4043 ms 1372 KB Time limit exceeded
22 Halted 0 ms 0 KB -