oj.uz

Submission #397535

# Submission time Handle Problem Language Result Execution time Memory
397535 2021-05-02T10:38:01 Z blue Swapping Cities (APIO20_swap) C++17
24 / 100
 2000 ms 351812 KB 
#include "swap.h"
#include <vector>
#include <algorithm>
using namespace std;

/*
Use Kruskal's algorithm.
For every node, compute sorted (by wt) list of edges that doubled its component's size.
Also compute the minimum edge wt that made it's component 'good'.

A component is good if it is not a single path.
*/

vector<int> W1;

vector<int> merges[100000]; //edge
vector<int> newcol[100000]; //color after merging
vector<int> goodEdge(100000, 2e9); //weight of smallest edge that made node's component good

void init(int N, int M, vector<int> U, vector<int> V, vector<int> W)
{
    W1 = W;

    int I[M];
    for(int i = 0; i < M; i++) I[i] = i;
    sort(I, I+M, [] (int x, int y)
    {
        return W1[x] < W1[y];
    });

    // for(int i: I) cerr << i << ' ';
    // cerr << '\n';

    vector<int> col(N);
    vector<int> col_list[N];
    vector<int> endpoints[N];

    for(int i = 0; i < N; i++)
    {
        col[i] = i;
        col_list[i].push_back(i);

        merges[i].push_back(0);
        newcol[i].push_back(i);

        for(int e = 0; e < 2; e++)
            endpoints[i].push_back(i);
    }

    for(int i = 0; i < M; i++)
    {
        int u = U[I[i]], v = V[I[i]], w = W[I[i]];
        // cerr << "cc:\n";
        // for(int j = 0; j < N; j++)
        // {
        //     for(int q: col_list[j]) cerr << q << ' ';
        //     cerr << '\n';
        // }
        // cerr << "wt = " << w << '\n';

        if(col[u] == col[v])
        {
            if(endpoints[ col[u] ].size() == 0) continue;
            for(int x: col_list[ col[u] ])
                goodEdge[x] = w;
            endpoints[ col[u] ].clear();
            continue;
        }

        if(col_list[u].size() < col_list[v].size())
            swap(u, v);


        bool flag = 1;
        if(goodEdge[u] == 2e9 && goodEdge[v] < 2e9)
        {
            endpoints[ col[u] ].clear();
            for(int x: col_list[col[u]])
                goodEdge[x] = w;
            flag = 0;
        }
        else if(goodEdge[u] < 2e9 && goodEdge[v] == 2e9)
        {
            endpoints[ col[v] ].clear();
            for(int x: col_list[col[v]])
                goodEdge[x] = w;
            flag = 0;
        }
        else if(goodEdge[u] < 2e9 && goodEdge[v] < 2e9)
            flag = 0;

        if(flag && (u == endpoints[col[u]][0] || u == endpoints[col[u]][1]) && (v == endpoints[col[v]][0] || v == endpoints[col[v]][1]))
        {
            if(u == endpoints[col[u]][1])
                swap(endpoints[col[u]][0], endpoints[col[u]][1]);

            if(v == endpoints[col[v]][1])
                swap(endpoints[col[v]][0], endpoints[col[v]][1]);

            endpoints[col[u]] = {endpoints[col[u]][1], endpoints[col[v]][1]};
        }
        else if(flag)
        {
            endpoints[ col[u] ].clear();
            for(int x: col_list[col[u]])
                goodEdge[x] = w;

            endpoints[ col[v] ].clear();
            for(int x: col_list[col[v]])
                goodEdge[x] = w;
        }

        int colV = col[v];
        for(int x: col_list[colV])
        {
            merges[x].push_back(w);
            newcol[x].push_back(col[u]);
            col_list[ col[u] ].push_back(x);
            col[x] = col[u];
        }
        col_list[colV].clear();
    }

    // for(int i = 0; i < N; i++)
    // {
    //     cerr << "i = " << i << '\n';
    //     cerr << goodEdge[i] << '\n';
    //     cerr << "merges: ";
    //     for(int m: merges[i]) cerr << m << ' ';
    //     cerr << '\n';
    //     cerr << "newcol; ";
    //     for(int n: newcol[i]) cerr << n << ' ';
    //     cerr << '\n';
    // }
}

int getMinimumFuelCapacity(int X, int Y)
{
    for(int i = 1; i <= 100000; i++);
    if(goodEdge[X] == 2e9) return -1;

    // cerr << "\n";
    // cerr << goodEdge[X] << '\n';
    // for(int i = 0; i < merges[X].size(); i++)
    // {
    //     cerr << merges[X][i] << ' ' << newcol[X][i] << '\n';
    // }
    // cerr << '\n';
    // cerr << goodEdge[Y] << '\n';
    // for(int i = 0; i < merges[Y].size(); i++)
    // {
    //     cerr << merges[Y][i] << ' ' << newcol[Y][i] << '\n';
    // }
    // cerr << '\n';


    int res = 2e9;

    for(int i = 0; i < merges[X].size(); i++)
        for(int j = 0; j < merges[Y].size(); j++)
            if(newcol[X][i] == newcol[Y][j])
                res = min(res, max(merges[X][i], merges[Y][j]));

    res = max(res, goodEdge[X]);

    return res;
}

Compilation message

swap.cpp: In function 'int getMinimumFuelCapacity(int, int)':
swap.cpp:159:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  159 |     for(int i = 0; i < merges[X].size(); i++)
      |                    ~~^~~~~~~~~~~~~~~~~~
swap.cpp:160:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  160 |         for(int j = 0; j < merges[Y].size(); j++)
      |                        ~~^~~~~~~~~~~~~~~~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 4 ms 5452 KB Output is correct
5 Correct 4 ms 5580 KB Output is correct
6 Correct 5 ms 5696 KB Output is correct
7 Correct 5 ms 5580 KB Output is correct
8 Correct 10 ms 7508 KB Output is correct
9 Correct 333 ms 36268 KB Output is correct
10 Correct 439 ms 43064 KB Output is correct
11 Correct 425 ms 43004 KB Output is correct
12 Correct 467 ms 45496 KB Output is correct
13 Execution timed out 2108 ms 351812 KB Time limit exceeded

Subtask #2
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 213 ms 27728 KB Output is correct
4 Correct 221 ms 28648 KB Output is correct
5 Correct 225 ms 28244 KB Output is correct
6 Correct 217 ms 28512 KB Output is correct
7 Correct 227 ms 28512 KB Output is correct
8 Correct 213 ms 27544 KB Output is correct
9 Correct 220 ms 28264 KB Output is correct
10 Correct 212 ms 27428 KB Output is correct

Subtask #3
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 4 ms 5452 KB Output is correct
5 Correct 4 ms 5580 KB Output is correct
6 Correct 5 ms 5696 KB Output is correct
7 Correct 5 ms 5580 KB Output is correct
8 Correct 10 ms 7508 KB Output is correct
9 Correct 3 ms 5320 KB Output is correct
10 Correct 6 ms 6220 KB Output is correct
11 Correct 5 ms 5708 KB Output is correct
12 Correct 6 ms 5708 KB Output is correct
13 Correct 5 ms 5672 KB Output is correct
14 Correct 6 ms 5836 KB Output is correct
15 Correct 5 ms 5708 KB Output is correct
16 Correct 5 ms 5580 KB Output is correct
17 Correct 10 ms 7632 KB Output is correct
18 Correct 6 ms 5964 KB Output is correct
19 Correct 8 ms 7116 KB Output is correct
20 Correct 5 ms 5708 KB Output is correct
21 Correct 10 ms 7756 KB Output is correct
22 Correct 5 ms 5708 KB Output is correct
23 Correct 7 ms 6348 KB Output is correct
24 Correct 5 ms 5708 KB Output is correct
25 Correct 8 ms 6604 KB Output is correct
26 Correct 5 ms 5708 KB Output is correct
27 Correct 11 ms 8140 KB Output is correct
28 Correct 15 ms 9220 KB Output is correct

Subtask #4
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5320 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 3 ms 5324 KB Output is correct
5 Correct 4 ms 5452 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 5 ms 5696 KB Output is correct
8 Correct 5 ms 5580 KB Output is correct
9 Correct 10 ms 7508 KB Output is correct
10 Correct 333 ms 36268 KB Output is correct
11 Correct 439 ms 43064 KB Output is correct
12 Correct 425 ms 43004 KB Output is correct
13 Correct 467 ms 45496 KB Output is correct
14 Execution timed out 2108 ms 351812 KB Time limit exceeded

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5324 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 4 ms 5452 KB Output is correct
5 Correct 4 ms 5580 KB Output is correct
6 Correct 5 ms 5696 KB Output is correct
7 Correct 5 ms 5580 KB Output is correct
8 Correct 10 ms 7508 KB Output is correct
9 Correct 333 ms 36268 KB Output is correct
10 Correct 439 ms 43064 KB Output is correct
11 Correct 425 ms 43004 KB Output is correct
12 Correct 467 ms 45496 KB Output is correct
13 Execution timed out 2108 ms 351812 KB Time limit exceeded

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5320 KB Output is correct
2 Correct 3 ms 5324 KB Output is correct
3 Correct 3 ms 5324 KB Output is correct
4 Correct 3 ms 5324 KB Output is correct
5 Correct 4 ms 5452 KB Output is correct
6 Correct 4 ms 5580 KB Output is correct
7 Correct 5 ms 5696 KB Output is correct
8 Correct 5 ms 5580 KB Output is correct
9 Correct 10 ms 7508 KB Output is correct
10 Correct 333 ms 36268 KB Output is correct
11 Correct 439 ms 43064 KB Output is correct
12 Correct 425 ms 43004 KB Output is correct
13 Correct 467 ms 45496 KB Output is correct
14 Execution timed out 2108 ms 351812 KB Time limit exceeded