oj.uz

Submission #16675

# Submission time Handle Problem Language Result Execution time Memory
16675 2015-09-05T10:39:40 Z suhgyuho_william Race (IOI11_race) C++
0 / 100
 6 ms 4988 KB 
#include "race.h"
#include <vector>
#include <algorithm>
using namespace std;
// frozen

int i,n,k;
int answer = 999999999;
vector<pair<int,int> > edge[200002];
bool check[200002];
int half_sum[1000002];
int sum1,sum2;
int tsum;

int find_middle(int x){
    return x;
}

void dfs(int v,long long sum,int cnt){
    int i,sizes;
    int nextv,cost;

    if(sum > k) return;
    check[v] = true;
    if(half_sum[sum] > cnt) half_sum[sum] = cnt;
    if(k%2 == 0 && sum == k/2 && tsum > cnt) tsum = cnt;

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

void race(int x){
    int i,sizes;
    int nextv,t;
    int v = find_middle(x);

    if(k%2 == 0) sum1 = sum2 = 999999999;
    check[v] = true;
    sizes = edge[v].size();
    for(i=0; i<=k; i++) half_sum[i] = 999999999;
    half_sum[0] = 0;

    for(i=0; i<sizes; i++){
        nextv = edge[v][i].first;
        if(check[nextv]) continue;
        tsum = 999999999;
        dfs(nextv,edge[v][i].second,1);
        if(tsum == 999999999) continue;
        if(sum1 == 999999999){
            sum1 = tsum;
        }else if(sum2 == 999999999){
            sum2 = tsum;
            if(sum1 > sum2) swap(sum1,sum2);
        }else if(!(sum2 < tsum)){
            sum2 = tsum;
            if(sum1 > sum2) swap(sum1,sum2);
        }
    }

    if(k%2 ==1) t = k/2;
    else t = (k/2)-1;
    for(i=0; i<=t; i++) if(half_sum[i] != 999999999 && half_sum[k-i] != 999999999 && answer > half_sum[i]+half_sum[k-i]) answer = half_sum[i]+half_sum[k-i];
    if(k%2 == 0 && sum1 != 999999999 && sum2 != 999999999 && answer > sum1+sum2) answer = sum1+sum2;


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

int best_path(int N, int K, int H[][2], int L[])
{
    int i;

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

    race(0);

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

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 4988 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 4988 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 22.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 4988 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 57.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 4988 KB Output isn't correct
2 Halted 0 ms 0 KB -