Submission #67476

# Submission time Handle Problem Language Result Execution time Memory
67476 2018-08-14T10:32:19 Z Kubalionzzale Dreaming (IOI13_dreaming) C++14
18 / 100
56 ms 11256 KB
#include "dreaming.h"

#include <iostream>
#include <vector>
#include <assert.h>

int component[100010] = { 0 };
int componentmin[100010] = { 0 };
int curmax[100010] = { 0 };
int n, m, l;
std::vector< std::vector< std::pair<int, int> > > g(100010);

void dfs(int index, int parent, int mark)
{
    for (int i = 0; i < g[index].size(); ++i)
    {
        int next = g[index][i].second;
        int nextVal = g[index][i].first;

        if (next != parent)
        {
            dfs(next, index, mark);
            curmax[index] = std::max(curmax[index], curmax[next] + nextVal);
        }
    }

    component[index] = mark;
}

void dfsout(int index, int parent, int pathSum)
{
    int max1 = pathSum, max2 = -1;
    for (int i = 0; i < g[index].size(); ++i)
    {
        int next = g[index][i].second;
        int nextVal = g[index][i].first;

        if (nextVal + curmax[next] > max1)
        {
            max2 = max1;
            max1 = nextVal + curmax[next];
        }
        else if (nextVal + curmax[next] > max2)
        {
            max2 = nextVal + curmax[next];
        }
    }

    for (int i = 0; i < g[index].size(); ++i)
    {
        int next = g[index][i].second;
        int nextVal = g[index][i].first;

        if (next != parent)
        {
            int val;
            if (nextVal + curmax[next] == max1)
            {
                curmax[next] = std::max(curmax[next], nextVal + max2);
                val = nextVal + max2;
            }
            else
            {
                curmax[next] = std::max(curmax[next], nextVal + max1);
                val = nextVal + max1;
            }

            dfsout(next, index, val);
        }
    }
}

int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
    n = N;
    m = M;
    l = L;

    for (int i = 0; i < m; ++i)
    {
        g[A[i]].push_back(std::make_pair(T[i], B[i]));
        g[B[i]].push_back(std::make_pair(T[i], A[i]));
    }

    int cnt = 1;
    for (int i = 0; i < n; ++i)
    {
        if (!component[i])
        {
            dfs(i, -1, cnt);
            dfsout(i, -1, 0);

            ++cnt;
        }
    }

    for (int i = 1; i < cnt; ++i)
    {
        componentmin[i] = 1e9 + 5;
    }

    for (int i = 0; i < n; ++i)
    {
        componentmin[component[i]] = std::min(componentmin[component[i]], curmax[i]);
    }

    int ans = 0;
    int max = -1;
    int maxindex;

    for (int i = 1; i < cnt; ++i)
    {
        if (componentmin[i] > max)
        {
            max = componentmin[i];
            maxindex = i;
        }
    }

    if (m == n - 1)
        return componentmin[1];

    for (int i = 1; i < cnt; ++i)
    {
        if (i != maxindex)
        {
            ans = std::max(ans, l + max + componentmin[i]);
        }
    }

    int max1 = -1, max2 = -1;
    for (int i = 1; i < cnt; ++i)
    {
        if (i != maxindex)
        {
            if (componentmin[i] > max1)
            {
                max2 = max1;
                max1 = componentmin[i];
            }
            else if (componentmin[i] > max2)
            {
                max2 = componentmin[i];
            }
        }
    }

    for (int i = 1; i < cnt; ++i)
    {
        if (i != maxindex)
        {
            if (componentmin[i] == max1)
            {
                if (max2 != -1)
                {
                    ans = std::max(ans, max2 + 2 * l + componentmin[i]);
                }
            }
            else
            {
                ans = std::max(ans, max1 + 2 * l + componentmin[i]);
            }
        }
    }

    return ans;
}

Compilation message

dreaming.cpp: In function 'void dfs(int, int, int)':
dreaming.cpp:15:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < g[index].size(); ++i)
                     ~~^~~~~~~~~~~~~~~~~
dreaming.cpp: In function 'void dfsout(int, int, int)':
dreaming.cpp:33:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < g[index].size(); ++i)
                     ~~^~~~~~~~~~~~~~~~~
dreaming.cpp:49:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < g[index].size(); ++i)
                     ~~^~~~~~~~~~~~~~~~~
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:124:9: warning: 'maxindex' may be used uninitialized in this function [-Wmaybe-uninitialized]
         if (i != maxindex)
         ^~
# Verdict Execution time Memory Grader output
1 Incorrect 56 ms 11256 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 56 ms 11256 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 56 ms 11256 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 24 ms 6016 KB Output is correct
2 Correct 27 ms 6096 KB Output is correct
3 Correct 22 ms 6008 KB Output is correct
4 Correct 29 ms 6140 KB Output is correct
5 Correct 23 ms 6008 KB Output is correct
6 Correct 27 ms 6136 KB Output is correct
7 Correct 28 ms 6144 KB Output is correct
8 Correct 32 ms 6008 KB Output is correct
9 Correct 27 ms 5880 KB Output is correct
10 Correct 26 ms 6140 KB Output is correct
11 Correct 4 ms 2688 KB Output is correct
12 Correct 6 ms 3840 KB Output is correct
13 Correct 7 ms 3968 KB Output is correct
14 Correct 6 ms 3840 KB Output is correct
15 Correct 6 ms 3968 KB Output is correct
16 Correct 6 ms 3840 KB Output is correct
17 Correct 6 ms 3712 KB Output is correct
18 Correct 7 ms 3968 KB Output is correct
19 Correct 6 ms 3840 KB Output is correct
20 Correct 4 ms 2688 KB Output is correct
21 Correct 4 ms 2688 KB Output is correct
22 Correct 3 ms 2688 KB Output is correct
23 Correct 6 ms 3840 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 56 ms 11256 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 56 ms 11256 KB Output isn't correct
2 Halted 0 ms 0 KB -