oj.uz

Submission #44646

# Submission time Handle Problem Language Result Execution time Memory
44646 2018-04-04T07:41:44 Z RayaBurong25_1 Network (BOI15_net) C++17
100 / 100
 1311 ms 195944 KB 
#include <stdio.h>
#include <vector>
#include <algorithm>
#include <cassert>
std::vector<int> AdjList[500005];
std::vector<int> Leaf;
int Root;
int H[500005];
int Pa[500005][20];
void dfs(int u, int pa, int h)
{
    H[u] = h;
    Pa[u][0] = pa;
    if (pa == 0)
        Root = u;
    int i, v, s = AdjList[u].size();
    for (i = 0; i < s; i++)
    {
        v = AdjList[u][i];
        if (v != pa)
        {
            dfs(v, u, h + 1);
        }
    }
    if (s == 1)
        Leaf.push_back(u);
}
int cnt;
int M[500005];
int lca(int u, int v)
{
    int i;
    if (H[v] > H[u])
        return lca(v, u);
    if (H[u] > H[v])
    {
        for (i = 19; i >= 0; i--)
        {
            if (H[Pa[u][i]] > H[v])
                u = Pa[u][i];
        }
        u = Pa[u][0];
    }
    if (u == v)
        return u;
    for (i = 19; i >= 0; i--)
    {
        if (Pa[u][i] != Pa[v][i])
        {
            u = Pa[u][i];
            v = Pa[v][i];
        }
    }
    u = Pa[u][0];
    return u;
}
void mark(int u, int v)
{
    // printf("mark u%d v%d lca%d\n", u, v, lca(u, v));
    M[u]++;
    M[v]++;
    M[lca(u, v)] -= 2;
}
void dfscheck(int u, int pa)
{
    int i, v, s = AdjList[u].size();
    for (i = 0; i < s; i++)
    {
        v = AdjList[u][i];
        if (v != pa)
        {
            dfscheck(v, u);
            M[u] += M[v];
        }
    }
    // printf("M[%d] = %d\n", u, M[u]);
    assert(M[u] >= 0);
    if (M[u] == 0 && pa != 0) cnt++;
}
int N;
int check()
{
    int i, j;
    for (i = 1; i <= N; i++)
        M[i] = 0;
    cnt = 0;
    for (i = 0, j = Leaf.size() - 1; i < j; i++, j--)
        mark(Leaf[i], Leaf[j]);
    if (i == j)
        mark(Leaf[i], Root);
    if (AdjList[1].size() > 1)
        dfscheck(1, 0);
    else
        dfscheck(AdjList[1][0], 0);
    return (cnt == 0);
}
int main()
{
    scanf("%d", &N);
    int i, j, u, v;
    for (i = 0; i < N - 1; i++)
    {
        scanf("%d %d", &u, &v);
        AdjList[u].push_back(v);
        AdjList[v].push_back(u);
    }
    if (AdjList[1].size() > 1)
        dfs(1, 0, 0);
    else
        dfs(AdjList[1][0], 0, 0);
    for (j = 1; j < 20; j++)
    {
        for (i = 1; i <= N; i++)
        {
            Pa[i][j] = Pa[Pa[i][j - 1]][j - 1];
        }
    }
    printf("%d\n", (Leaf.size() + 1)/2);
    // if (check())
    // {
    //     for (i = 0, j = Leaf.size() - 1; i < j; i++, j--)
    //         printf("%d %d\n", Leaf[i], Leaf[j]);
    //     if (i == j)
    //         printf("%d %d\n", Leaf[i], Root);
    // }
    // else
    // {
    //     Leaf.push_back(Leaf[0]);
    //     Leaf.erase(Leaf.begin());
    //     if (!check())
    //         assert(1 == 0);
    //     for (i = 0, j = Leaf.size() - 1; i < j; i++, j--)
    //         printf("%d %d\n", Leaf[i], Leaf[j]);
    //     if (i == j)
    //         printf("%d %d\n", Leaf[i], Root);
    // }
    int cnt = 0;
    while (!check())
    {
        if (Leaf.size() < 10)
            std::next_permutation(Leaf.begin(), Leaf.end());
        else
        {
            Leaf.push_back(Leaf[0]);
            Leaf.erase(Leaf.begin());
        }
    }
    if (cnt == Leaf.size())
        assert(1 == 0);
    for (i = 0, j = Leaf.size() - 1; i < j; i++, j--)
        printf("%d %d\n", Leaf[i], Leaf[j]);
    if (i == j)
        printf("%d %d\n", Leaf[i], Root);
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:118:39: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=]
     printf("%d\n", (Leaf.size() + 1)/2);
                    ~~~~~~~~~~~~~~~~~~~^
net.cpp:148:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (cnt == Leaf.size())
         ~~~~^~~~~~~~~~~~~~
net.cpp:99:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &N);
     ~~~~~^~~~~~~~~~
net.cpp:103:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &u, &v);
         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12024 KB Output is correct
2 Correct 11 ms 12132 KB Output is correct
3 Correct 11 ms 12208 KB Output is correct
4 Correct 11 ms 12208 KB Output is correct
5 Correct 11 ms 12208 KB Output is correct
6 Correct 12 ms 12208 KB Output is correct
7 Correct 13 ms 12244 KB Output is correct
8 Correct 12 ms 12244 KB Output is correct
9 Correct 15 ms 12244 KB Output is correct
10 Correct 15 ms 12244 KB Output is correct
11 Correct 15 ms 12244 KB Output is correct
12 Correct 12 ms 12320 KB Output is correct
13 Correct 14 ms 12320 KB Output is correct
14 Correct 14 ms 12320 KB Output is correct
15 Correct 12 ms 12320 KB Output is correct
16 Correct 13 ms 12320 KB Output is correct
17 Correct 12 ms 12320 KB Output is correct
18 Correct 12 ms 12320 KB Output is correct
19 Correct 12 ms 12320 KB Output is correct
20 Correct 14 ms 12368 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12024 KB Output is correct
2 Correct 11 ms 12132 KB Output is correct
3 Correct 11 ms 12208 KB Output is correct
4 Correct 11 ms 12208 KB Output is correct
5 Correct 11 ms 12208 KB Output is correct
6 Correct 12 ms 12208 KB Output is correct
7 Correct 13 ms 12244 KB Output is correct
8 Correct 12 ms 12244 KB Output is correct
9 Correct 15 ms 12244 KB Output is correct
10 Correct 15 ms 12244 KB Output is correct
11 Correct 15 ms 12244 KB Output is correct
12 Correct 12 ms 12320 KB Output is correct
13 Correct 14 ms 12320 KB Output is correct
14 Correct 14 ms 12320 KB Output is correct
15 Correct 12 ms 12320 KB Output is correct
16 Correct 13 ms 12320 KB Output is correct
17 Correct 12 ms 12320 KB Output is correct
18 Correct 12 ms 12320 KB Output is correct
19 Correct 12 ms 12320 KB Output is correct
20 Correct 14 ms 12368 KB Output is correct
21 Correct 14 ms 12368 KB Output is correct
22 Correct 17 ms 12524 KB Output is correct
23 Correct 13 ms 12524 KB Output is correct
24 Correct 14 ms 12540 KB Output is correct
25 Correct 13 ms 12540 KB Output is correct
26 Correct 13 ms 12556 KB Output is correct
27 Correct 17 ms 12556 KB Output is correct
28 Correct 14 ms 12596 KB Output is correct
29 Correct 17 ms 12596 KB Output is correct
30 Correct 12 ms 12596 KB Output is correct
31 Correct 14 ms 12640 KB Output is correct
32 Correct 14 ms 12640 KB Output is correct
33 Correct 15 ms 12640 KB Output is correct
34 Correct 12 ms 12640 KB Output is correct
35 Correct 12 ms 12640 KB Output is correct
36 Correct 13 ms 12640 KB Output is correct
37 Correct 13 ms 12640 KB Output is correct
38 Correct 16 ms 12640 KB Output is correct
39 Correct 13 ms 12640 KB Output is correct
40 Correct 12 ms 12640 KB Output is correct
41 Correct 12 ms 12640 KB Output is correct
42 Correct 12 ms 12640 KB Output is correct
43 Correct 13 ms 12640 KB Output is correct
44 Correct 14 ms 12640 KB Output is correct
45 Correct 12 ms 12640 KB Output is correct
46 Correct 14 ms 12640 KB Output is correct
47 Correct 12 ms 12640 KB Output is correct
48 Correct 13 ms 12640 KB Output is correct
49 Correct 13 ms 12736 KB Output is correct
50 Correct 15 ms 12736 KB Output is correct
51 Correct 12 ms 12736 KB Output is correct
52 Correct 12 ms 12736 KB Output is correct
53 Correct 16 ms 12768 KB Output is correct
54 Correct 13 ms 12768 KB Output is correct
55 Correct 13 ms 12768 KB Output is correct
56 Correct 12 ms 12768 KB Output is correct
57 Correct 13 ms 12768 KB Output is correct
58 Correct 16 ms 12824 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 12024 KB Output is correct
2 Correct 11 ms 12132 KB Output is correct
3 Correct 11 ms 12208 KB Output is correct
4 Correct 11 ms 12208 KB Output is correct
5 Correct 11 ms 12208 KB Output is correct
6 Correct 12 ms 12208 KB Output is correct
7 Correct 13 ms 12244 KB Output is correct
8 Correct 12 ms 12244 KB Output is correct
9 Correct 15 ms 12244 KB Output is correct
10 Correct 15 ms 12244 KB Output is correct
11 Correct 15 ms 12244 KB Output is correct
12 Correct 12 ms 12320 KB Output is correct
13 Correct 14 ms 12320 KB Output is correct
14 Correct 14 ms 12320 KB Output is correct
15 Correct 12 ms 12320 KB Output is correct
16 Correct 13 ms 12320 KB Output is correct
17 Correct 12 ms 12320 KB Output is correct
18 Correct 12 ms 12320 KB Output is correct
19 Correct 12 ms 12320 KB Output is correct
20 Correct 14 ms 12368 KB Output is correct
21 Correct 14 ms 12368 KB Output is correct
22 Correct 17 ms 12524 KB Output is correct
23 Correct 13 ms 12524 KB Output is correct
24 Correct 14 ms 12540 KB Output is correct
25 Correct 13 ms 12540 KB Output is correct
26 Correct 13 ms 12556 KB Output is correct
27 Correct 17 ms 12556 KB Output is correct
28 Correct 14 ms 12596 KB Output is correct
29 Correct 17 ms 12596 KB Output is correct
30 Correct 12 ms 12596 KB Output is correct
31 Correct 14 ms 12640 KB Output is correct
32 Correct 14 ms 12640 KB Output is correct
33 Correct 15 ms 12640 KB Output is correct
34 Correct 12 ms 12640 KB Output is correct
35 Correct 12 ms 12640 KB Output is correct
36 Correct 13 ms 12640 KB Output is correct
37 Correct 13 ms 12640 KB Output is correct
38 Correct 16 ms 12640 KB Output is correct
39 Correct 13 ms 12640 KB Output is correct
40 Correct 12 ms 12640 KB Output is correct
41 Correct 12 ms 12640 KB Output is correct
42 Correct 12 ms 12640 KB Output is correct
43 Correct 13 ms 12640 KB Output is correct
44 Correct 14 ms 12640 KB Output is correct
45 Correct 12 ms 12640 KB Output is correct
46 Correct 14 ms 12640 KB Output is correct
47 Correct 12 ms 12640 KB Output is correct
48 Correct 13 ms 12640 KB Output is correct
49 Correct 13 ms 12736 KB Output is correct
50 Correct 15 ms 12736 KB Output is correct
51 Correct 12 ms 12736 KB Output is correct
52 Correct 12 ms 12736 KB Output is correct
53 Correct 16 ms 12768 KB Output is correct
54 Correct 13 ms 12768 KB Output is correct
55 Correct 13 ms 12768 KB Output is correct
56 Correct 12 ms 12768 KB Output is correct
57 Correct 13 ms 12768 KB Output is correct
58 Correct 16 ms 12824 KB Output is correct
59 Correct 942 ms 75488 KB Output is correct
60 Correct 1107 ms 88532 KB Output is correct
61 Correct 13 ms 88532 KB Output is correct
62 Correct 12 ms 88532 KB Output is correct
63 Correct 780 ms 88532 KB Output is correct
64 Correct 18 ms 88532 KB Output is correct
65 Correct 33 ms 88532 KB Output is correct
66 Correct 844 ms 88532 KB Output is correct
67 Correct 1311 ms 119524 KB Output is correct
68 Correct 1201 ms 127128 KB Output is correct
69 Correct 24 ms 127128 KB Output is correct
70 Correct 246 ms 127128 KB Output is correct
71 Correct 884 ms 127128 KB Output is correct
72 Correct 849 ms 127128 KB Output is correct
73 Correct 291 ms 127128 KB Output is correct
74 Correct 1123 ms 132024 KB Output is correct
75 Correct 64 ms 132024 KB Output is correct
76 Correct 894 ms 143132 KB Output is correct
77 Correct 872 ms 150000 KB Output is correct
78 Correct 71 ms 150000 KB Output is correct
79 Correct 1177 ms 168072 KB Output is correct
80 Correct 16 ms 168072 KB Output is correct
81 Correct 297 ms 168072 KB Output is correct
82 Correct 910 ms 168072 KB Output is correct
83 Correct 1002 ms 168500 KB Output is correct
84 Correct 1294 ms 175140 KB Output is correct
85 Correct 954 ms 181744 KB Output is correct
86 Correct 959 ms 189548 KB Output is correct
87 Correct 996 ms 195944 KB Output is correct