oj.uz

Submission #16693

# Submission time Handle Problem Language Result Execution time Memory
16693 2015-09-06T07:18:00 Z suhgyuho_william Race (IOI11_race) C++
21 / 100
 3000 ms 12716 KB 
#include "race.h"
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;

int n,k;
int answer = 999999999;
vector<pair<int,int> > edge[200002];
queue<pair<int,int> > q,qt;
int root[1000002],small[1000002];
bool check[200002];
queue<int> qv;
int downcnt[200002];
int max_subtree[200002];

int j,nextv,tmp;
pair<int,int> top;

int make_qv(int x){
    int i;

    check[x] = true;
    qv.push(x);
    downcnt[x] = max_subtree[x] = 0;
    for(i=0; i<edge[x].size(); i++){
        nextv = edge[x][i].first;
        if(!check[nextv]){
            tmp = make_qv(nextv);
            downcnt[x] += tmp;
            if(max_subtree[x] < tmp) max_subtree[x] = tmp;
        }
    }
    check[x] = false;
    return (downcnt[x]+1);
}

int find_middle(int x){
    int i,below_x;
    int big = 0,v;

    below_x = make_qv(x);
    while(!qv.empty()){
        v = qv.front();
        tmp = max(below_x - max_subtree[v],max_subtree[v]+1);
        if(big < tmp){
            big = tmp;
            x = v;
        }
        qv.pop();
    }

    return x;
}

void dfs(int v,int sum,int cnt){
    int i;

    if(sum > k) return;
    check[v] = true;
    q.push(make_pair(sum,cnt));
    qt.push(make_pair(sum,cnt));

    for(i=0; i<edge[v].size(); i++){
        nextv = edge[v][i].first;
        if(check[nextv]) continue;
        dfs(nextv,sum+edge[v][i].second,cnt+1);
    }
    check[v] = false;
}

// T(n) = 2T(n/2) + O(n);

void race(int x){
    int i;
    int v = find_middle(x);

    check[v] = true;

    root[0] = v;
    small[0] = 0;
    for(i=0; i<edge[v].size(); i++){
        nextv = edge[v][i].first;
        if(check[nextv]) continue;
        dfs(nextv,edge[v][i].second,1);

        while(!q.empty()){
            top = q.front();
            if(root[k-top.first] == v) answer = min(answer,small[k-top.first] + top.second);
            q.pop();
        }
        while(!qt.empty()){
            top = qt.front();
            qt.pop();

            if(root[top.first] != v){
                root[top.first] = v;
                small[top.first] = top.second;
            }else if(small[top.first] > top.second) small[top.first] = top.second;
        }
    }

    for(i=0; i<edge[v].size(); i++){
        nextv = edge[v][i].first;
        if(!check[nextv]) race(nextv);
    }
}

int best_path(int N, int K, int H[][2], int L[])
{
    n = N; k = K;
    for(j=0; j<n-1; j++){
        edge[H[j][0]].push_back(make_pair(H[j][1],L[j]));
        edge[H[j][1]].push_back(make_pair(H[j][0],L[j]));
    }
    for(j=0; j<=k; j++) root[j] = -1;

    race(0);

    if(answer == 999999999) answer = -1;
    return answer;
}

Compilation message

race.cpp: In function 'int make_qv(int)':
race.cpp:26:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0; i<edge[x].size(); i++){
              ~^~~~~~~~~~~~~~~
race.cpp: In function 'int find_middle(int)':
race.cpp:39:9: warning: unused variable 'i' [-Wunused-variable]
     int i,below_x;
         ^
race.cpp: In function 'void dfs(int, int, int)':
race.cpp:64:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0; i<edge[v].size(); i++){
              ~^~~~~~~~~~~~~~~
race.cpp: In function 'void race(int)':
race.cpp:82:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0; i<edge[v].size(); i++){
              ~^~~~~~~~~~~~~~~
race.cpp:103:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0; i<edge[v].size(); i++){
              ~^~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 5 ms 5092 KB Output is correct
3 Correct 5 ms 5168 KB Output is correct
4 Correct 5 ms 5244 KB Output is correct
5 Correct 5 ms 5320 KB Output is correct
6 Correct 6 ms 5320 KB Output is correct
7 Correct 5 ms 5356 KB Output is correct
8 Correct 5 ms 5356 KB Output is correct
9 Correct 5 ms 5356 KB Output is correct
10 Correct 6 ms 5356 KB Output is correct
11 Correct 7 ms 5356 KB Output is correct
12 Correct 6 ms 5484 KB Output is correct
13 Correct 6 ms 5484 KB Output is correct
14 Correct 7 ms 5484 KB Output is correct
15 Correct 5 ms 5484 KB Output is correct
16 Correct 6 ms 5500 KB Output is correct
17 Correct 5 ms 5500 KB Output is correct
18 Correct 6 ms 5500 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 5 ms 5092 KB Output is correct
3 Correct 5 ms 5168 KB Output is correct
4 Correct 5 ms 5244 KB Output is correct
5 Correct 5 ms 5320 KB Output is correct
6 Correct 6 ms 5320 KB Output is correct
7 Correct 5 ms 5356 KB Output is correct
8 Correct 5 ms 5356 KB Output is correct
9 Correct 5 ms 5356 KB Output is correct
10 Correct 6 ms 5356 KB Output is correct
11 Correct 7 ms 5356 KB Output is correct
12 Correct 6 ms 5484 KB Output is correct
13 Correct 6 ms 5484 KB Output is correct
14 Correct 7 ms 5484 KB Output is correct
15 Correct 5 ms 5484 KB Output is correct
16 Correct 6 ms 5500 KB Output is correct
17 Correct 5 ms 5500 KB Output is correct
18 Correct 6 ms 5500 KB Output is correct
19 Correct 5 ms 5500 KB Output is correct
20 Correct 6 ms 5500 KB Output is correct
21 Correct 34 ms 5500 KB Output is correct
22 Correct 20 ms 11772 KB Output is correct
23 Correct 19 ms 11772 KB Output is correct
24 Correct 20 ms 12072 KB Output is correct
25 Correct 64 ms 12072 KB Output is correct
26 Correct 17 ms 12072 KB Output is correct
27 Correct 18 ms 12072 KB Output is correct
28 Correct 21 ms 12072 KB Output is correct
29 Correct 32 ms 12072 KB Output is correct
30 Correct 34 ms 12072 KB Output is correct
31 Correct 53 ms 12072 KB Output is correct
32 Correct 68 ms 12072 KB Output is correct
33 Correct 46 ms 12072 KB Output is correct
34 Correct 20 ms 12072 KB Output is correct
35 Correct 21 ms 12072 KB Output is correct
36 Correct 22 ms 12716 KB Output is correct
37 Correct 43 ms 12716 KB Output is correct
38 Correct 46 ms 12716 KB Output is correct

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 5 ms 5092 KB Output is correct
3 Correct 5 ms 5168 KB Output is correct
4 Correct 5 ms 5244 KB Output is correct
5 Correct 5 ms 5320 KB Output is correct
6 Correct 6 ms 5320 KB Output is correct
7 Correct 5 ms 5356 KB Output is correct
8 Correct 5 ms 5356 KB Output is correct
9 Correct 5 ms 5356 KB Output is correct
10 Correct 6 ms 5356 KB Output is correct
11 Correct 7 ms 5356 KB Output is correct
12 Correct 6 ms 5484 KB Output is correct
13 Correct 6 ms 5484 KB Output is correct
14 Correct 7 ms 5484 KB Output is correct
15 Correct 5 ms 5484 KB Output is correct
16 Correct 6 ms 5500 KB Output is correct
17 Correct 5 ms 5500 KB Output is correct
18 Correct 6 ms 5500 KB Output is correct
19 Execution timed out 3037 ms 12716 KB Time limit exceeded
20 Halted 0 ms 0 KB -

Subtask #4
0 / 57.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 4984 KB Output is correct
2 Correct 5 ms 5092 KB Output is correct
3 Correct 5 ms 5168 KB Output is correct
4 Correct 5 ms 5244 KB Output is correct
5 Correct 5 ms 5320 KB Output is correct
6 Correct 6 ms 5320 KB Output is correct
7 Correct 5 ms 5356 KB Output is correct
8 Correct 5 ms 5356 KB Output is correct
9 Correct 5 ms 5356 KB Output is correct
10 Correct 6 ms 5356 KB Output is correct
11 Correct 7 ms 5356 KB Output is correct
12 Correct 6 ms 5484 KB Output is correct
13 Correct 6 ms 5484 KB Output is correct
14 Correct 7 ms 5484 KB Output is correct
15 Correct 5 ms 5484 KB Output is correct
16 Correct 6 ms 5500 KB Output is correct
17 Correct 5 ms 5500 KB Output is correct
18 Correct 6 ms 5500 KB Output is correct
19 Correct 5 ms 5500 KB Output is correct
20 Correct 6 ms 5500 KB Output is correct
21 Correct 34 ms 5500 KB Output is correct
22 Correct 20 ms 11772 KB Output is correct
23 Correct 19 ms 11772 KB Output is correct
24 Correct 20 ms 12072 KB Output is correct
25 Correct 64 ms 12072 KB Output is correct
26 Correct 17 ms 12072 KB Output is correct
27 Correct 18 ms 12072 KB Output is correct
28 Correct 21 ms 12072 KB Output is correct
29 Correct 32 ms 12072 KB Output is correct
30 Correct 34 ms 12072 KB Output is correct
31 Correct 53 ms 12072 KB Output is correct
32 Correct 68 ms 12072 KB Output is correct
33 Correct 46 ms 12072 KB Output is correct
34 Correct 20 ms 12072 KB Output is correct
35 Correct 21 ms 12072 KB Output is correct
36 Correct 22 ms 12716 KB Output is correct
37 Correct 43 ms 12716 KB Output is correct
38 Correct 46 ms 12716 KB Output is correct
39 Execution timed out 3037 ms 12716 KB Time limit exceeded
40 Halted 0 ms 0 KB -