Submission #739976

# Submission time Handle Problem Language Result Execution time Memory
739976 2023-05-11T19:23:39 Z danikoynov Parking (CEOI22_parking) C++14
35 / 100
337 ms 106932 KB
/**
 ____ ____ ____ ____ ____ ____
||l |||e |||i |||n |||a |||d ||
||__|||__|||__|||__|||__|||__||
|/__\|/__\|/__\|/__\|/__\|/__\|

**/

#include<bits/stdc++.h>
#define endl '\n'

using namespace std;
typedef long long ll;

void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}

const int maxn = 2e5 + 10;
int n, m, t[maxn][2], sz[maxn];
set < int > pos[maxn];
vector < int > g[2 * maxn];
vector < pair < int, int > > ans;
int used[maxn];
vector < int > path;
void dfs(int v)
{
    used[v] = 1;
    path.push_back(v);
    for (int u : g[v])
    {
        if (used[u])
            continue;
        dfs(u);
    }
}


void move_at(int i, int j)
{
    t[j][sz[j]] = t[i][sz[i] - 1];
    t[i][sz[i] - 1] = 0;
    sz[i] --;
    sz[j] ++;
    ans.push_back({i, j});
}

void solve_chain(vector < int > ch)
{

    deque < int > dq;
    for (int v : ch)
        dq.push_back(v);

        while(!dq.empty())
        {
            if (dq.size() == 2)
            {
                move_at(dq[0], dq[1]);
                dq.pop_front();
                dq.pop_front();
                break;
            }
            if (dq[1] > m)
            {
                move_at(dq[1] - m, dq[0]);
                dq.pop_front();
                dq.pop_front();
            }
            else
            {
                move_at(dq[dq.size() - 2] - m, dq.back());
                dq.pop_back();
                dq.pop_back();
            }
            /**for (int i =0 ; i < dq.size(); i ++)
                cout << dq[i] << " ";
            cout << endl;*/

        }
    /**if (ch[1] <= m)
        reverse(ch.begin(), ch.end());
        for (int i = 0; i < ch.size(); i ++)
            cout << ch[i] << " ";
        cout << endl;
    for (int i = 1; i < ch.size(); i += 2)
    {
        int p1 = ch[i - 1], p2 = ch[i], j = 0;
        if (p2 > m)
        {
            p2 -= m;
            j = 1;
        }

        t[p1][1] = t[p2][j];
        t[p2][j] = 0;
        ans.push_back({p2, p1});
        sz[p2] --;
        sz[p1] ++;

    }*/
}

void solve()
{
    cin >> n >> m;
    for (int i = 1; i <= m; i ++)
    {
        cin >> t[i][0] >> t[i][1];
    }

    for (int i = 1; i <= m; i ++)
    {
        if (t[i][0] == t[i][1] && t[i][0] != 0)
            continue;

                if (t[i][0] != 0)
            sz[i] ++;
            if (t[i][1] != 0)
                sz[i] ++;
        for (int j = 0; j < sz[i]; j ++)
        {
            pos[t[i][j]].insert(j * m + i);
        }

        if (sz[i] == 2)
        {
            g[i].push_back(m + i);
            g[m + i].push_back(i);
        }
    }

    for (int i = 1; i <= n; i ++)
    {
        int l = *pos[i].begin();
        pos[i].erase(l);
        int r = *pos[i].begin();
        pos[i].erase(r);
        g[l].push_back(r);
        g[r].push_back(l);
    }


    queue < vector < int > > chn, cyc;
    for (int i = 1; i <= 2 * m; i ++)
    {
        if (!used[i] && g[i].size() == 1)
        {
            path.clear();
            dfs(i);
                chn.push(path);
        }
    }

    for (int i = 1; i <= 2 * m; i ++)
    {
        if (!used[i] && g[i].size() > 0)
        {
            path.clear();
            dfs(i);
                cyc.push(path);
        }
    }

    while(true)
    {
        if (!chn.empty())
        {
            path = chn.front();
        /// cout << path.size() << endl;
            chn.pop();
            int up = -1;
            for (int i = 1; i < path.size(); i ++)
            {
                if (path[i] > m && path[i - 1] > m)
                {
                    up = i - 1;
                    break;
                }
            }

            if (up == -1)
            {
                solve_chain(path);
            }
            else
            {
                int cur = 1;
                while(cur <= m && t[cur][0] != 0)
                    cur ++;
                if (cur > m)
                {
                    cout << -1 << endl;
                    exit(0);
                }
                t[cur][0] = t[cur][1] = t[path[up] - m][1];
                t[path[up] - m][1] = 0;
                t[path[up + 1] - m][1] = 0;
                sz[path[up] - m] --;
                sz[path[up + 1] - m] --;
                sz[cur] = 2;
                ans.push_back({path[up] - m, cur});
                ans.push_back({path[up + 1] - m, cur});

                vector < int > left, right;
                for (int i = 0; i < up; i ++)
                    left.push_back(path[i]);
                for (int i = up + 2; i < path.size(); i ++)
                    right.push_back(path[i]);
                chn.push(left);
                chn.push(right);
            }
        }
        else
        if (!cyc.empty())
        {
            path = cyc.front();
            cyc.pop();
            vector < int > db;
            for (int i = 1; i < path.size(); i ++)
            {
                              if (path[i] > m && path[i - 1] > m)
                {
                    db.push_back(i - 1);
                    break;
                }
            }

            if (db.size() == 0)
            {
                int idx = 0;
                while(true)
                {
                    int row1 = path[idx];
                    int row2 = path[idx + 1];
                    if (row1 > m)
                        row1 -= m;
                    if (row2 > m)
                        row2 -= m;
                    if (row1 == row2)
                        idx ++;
                    else
                    {
                        break;
                    }
                }

                                int cur = 1;
                while(cur <= m && t[cur][0] != 0)
                    cur ++;
                if (cur > m)
                {
                    cout << -1 << endl;
                    exit(0);
                }
                vector < int > new_chain;
                if (path[idx] > m)
                {
                    //cout << path[idx] << " : " << path[idx + 1] << endl;
                    move_at(path[idx] - m, cur);
                    new_chain.push_back(cur);
                    for (int i = idx + 1; i < path.size(); i ++)
                        new_chain.push_back(path[i]);
                    for (int i = 0; i < idx; i ++)
                        new_chain.push_back(path[i]);
                       /** for (int i = 0; i < new_chain.size(); i ++)
                            cout << new_chain[i] << " ";
                        cout << endl;*/
                }
                else
                {
                    move_at(path[idx + 1] - m, cur);
                    new_chain.push_back(cur);
                    for (int i = idx; i >= 0; i --)
                        new_chain.push_back(path[i]);
                    for (int i = (int)(path.size()) - 1; i > idx + 1; i --)
                        new_chain.push_back(path[i]);
                }
                chn.push(new_chain);

            }
            else
            if (db.size() > 0)
            {
                ///cout << "here" << endl;
                                int cur = 1;
                while(cur <= m && t[cur][0] != 0)
                    cur ++;
                if (cur > m)
                {
                    cout << -1 << endl;
                    exit(0);
                }
                int up = db[0];

                t[cur][0] = t[cur][1] = t[path[up] - m][1];
                t[path[up] - m][1] = 0;
                t[path[up + 1] - m][1] = 0;
                sz[path[up] - m] --;
                sz[path[up + 1] - m] --;
                sz[cur] = 2;
                ans.push_back({path[up] - m, cur});
                ans.push_back({path[up + 1] - m, cur});


                vector < int > new_chain;
                for (int i = up - 1; i >= 0; i --)
                    new_chain.push_back(path[i]);
                for (int i = (int)(path.size()) - 1; i > up + 1; i --)
                    new_chain.push_back(path[i]);
                chn.push(new_chain);

            }
            /**else
            {
                int
            }*/
            ///cout << "Here" << endl;
        }
        else
        {
            break;
        }
    }

    cout << ans.size() << endl;
    for (pair < int, int > cur : ans)
    {
        cout << cur.first << " " << cur.second << endl;
    }
}

int main()
{
    solve();
    return 0;
}
/**
3 5
1 2
3 2
1 3
0 0

3 4
3 0
1 3
2 0
1 2


*/

Compilation message

Main.cpp: In function 'void solve_chain(std::vector<int>)':
Main.cpp:55:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   55 |     for (int v : ch)
      |     ^~~
Main.cpp:58:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   58 |         while(!dq.empty())
      |         ^~~~~
Main.cpp: In function 'void solve()':
Main.cpp:176:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  176 |             for (int i = 1; i < path.size(); i ++)
      |                             ~~^~~~~~~~~~~~~
Main.cpp:211:40: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  211 |                 for (int i = up + 2; i < path.size(); i ++)
      |                                      ~~^~~~~~~~~~~~~
Main.cpp:223:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  223 |             for (int i = 1; i < path.size(); i ++)
      |                             ~~^~~~~~~~~~~~~
Main.cpp:265:45: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  265 |                     for (int i = idx + 1; i < path.size(); i ++)
      |                                           ~~^~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 9 ms 19028 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Correct 10 ms 19028 KB Output is correct
4 Correct 10 ms 19028 KB Output is correct
5 Correct 10 ms 19036 KB Output is correct
6 Correct 10 ms 19104 KB Output is correct
7 Correct 10 ms 19028 KB Output is correct
8 Correct 10 ms 19104 KB Output is correct
9 Correct 10 ms 19028 KB Output is correct
10 Correct 10 ms 19028 KB Output is correct
# Verdict Execution time Memory Grader output
1 Runtime error 200 ms 63576 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 11 ms 19156 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Correct 10 ms 19284 KB Output is correct
4 Correct 11 ms 19284 KB Output is correct
5 Correct 11 ms 19284 KB Output is correct
6 Correct 11 ms 19284 KB Output is correct
7 Correct 11 ms 19284 KB Output is correct
8 Correct 10 ms 19180 KB Output is correct
9 Correct 11 ms 19284 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 11 ms 19156 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Correct 10 ms 19284 KB Output is correct
4 Correct 11 ms 19284 KB Output is correct
5 Correct 11 ms 19284 KB Output is correct
6 Correct 11 ms 19284 KB Output is correct
7 Correct 11 ms 19284 KB Output is correct
8 Correct 10 ms 19180 KB Output is correct
9 Correct 11 ms 19284 KB Output is correct
10 Runtime error 337 ms 106932 KB Execution killed with signal 11
11 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 11 ms 19156 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 9 ms 19028 KB Output is correct
2 Correct 10 ms 19028 KB Output is correct
3 Correct 10 ms 19028 KB Output is correct
4 Correct 10 ms 19028 KB Output is correct
5 Correct 10 ms 19036 KB Output is correct
6 Correct 10 ms 19104 KB Output is correct
7 Correct 10 ms 19028 KB Output is correct
8 Correct 10 ms 19104 KB Output is correct
9 Correct 10 ms 19028 KB Output is correct
10 Correct 10 ms 19028 KB Output is correct
11 Runtime error 200 ms 63576 KB Execution killed with signal 11
12 Halted 0 ms 0 KB -