Submission #238602

#	Time	Username	Problem	Language	Result	Execution time	Memory
238602		Ruxandra985	Race (IOI11_race)	C++14	0 / 100	14 ms	14464 KiB

race

#include <bits/stdc++.h>
#include "race.h"
#define DIMN 200010
#define MAX_N 500000
using namespace std;

vector < pair <int,int> > v[DIMN];
set < pair <int,int> > per[DIMN];
int sub[DIMN] , f[DIMN] , add[DIMN] , distanta[DIMN];
int sol;

void precalc (int nod , int tt){
    int i , vecin;

    sub[nod] = 1;
    for (i = 0 ; i < v[nod].size() ; i++){
        vecin = v[nod][i].first;
        if (vecin != tt && !f[vecin]){
            precalc (vecin , nod);
            sub[nod] += sub[vecin];
        }
    }

}

void dfs (int nod , int tt , int k){
    int i , vecin , maxi = 0 , fiu , rms;
    set < pair <int,int> > :: iterator aux;

    for (i = 0 ; i < v[nod].size() ; i++){
        vecin = v[nod][i].first;
        if (vecin != tt && sub[vecin] > maxi){
            maxi = sub[vecin];
            fiu = vecin;
        }
    }


    for (i = 0 ; i < v[nod].size() ; i++){
        vecin = v[nod][i].first;
        if (vecin != tt){
            dfs (vecin , nod , k);
            add[vecin] += v[nod][i].second;
            distanta[vecin]++;
        }
    }


    if (maxi){

        per[nod].swap(per[fiu]);
        add[nod] = add[fiu];
        distanta[nod] = distanta[fiu];

        per[nod].insert(make_pair(0 , 0));

        for (i = 0 ; i < v[nod].size() ; i++){
            vecin = v[nod][i].first;
            if (vecin != tt && vecin != fiu){


                per[nod].insert(make_pair(add[vecin] - add[nod] , distanta[vecin] - distanta[nod]));


                /// sa zicem ca nod ar fi lca - ul , un capat pana acum , unul in vecin

                for (set <pair <int,int> > :: iterator it = per[vecin].begin() ; it != per[vecin].end() ; it++){

                    if (it->first + add[vecin] > k)
                        continue;

                    rms = k - (it->first + add[vecin]) - add[nod];

                    aux = per[nod].upper_bound(make_pair(rms , 0));

                    if (aux->first == rms){

                        sol = min(sol , it->second + distanta[vecin] + aux->second + distanta[nod]);

                    }

                }



                /// vezi cum le unesti

                for (set <pair <int,int> > :: iterator it = per[vecin].begin() ; it != per[vecin].end() ; it++){

                    if (it->first + add[vecin] > k)
                        continue; /// nu imi pasa


                    per[nod].insert(make_pair(it->first + add[vecin] - add[nod] , it->second + distanta[vecin] - distanta[nod]));


                }


            }
        }


    }

    aux = per[nod].upper_bound(make_pair(k - add[nod] , 0));
    if (aux->first == k - add[nod])
        sol = min(sol , aux->second + distanta[nod]);

    //printf ("%d %d\n" , nod , add[nod]);


}

int best_path(int n, int k, int h[][2], int l[]){
    int i;

    for (i = 0 ; i < n - 1 ; i++){

        h[i][1]++;
        h[i][0]++;

        v[h[i][0]].push_back(make_pair(h[i][1] , l[i]));
        v[h[i][1]].push_back(make_pair(h[i][0] , l[i]));

    }

    precalc (1 , 0);

    sol = 2000000000;

    dfs (1 , 0 , k);

    return (sol == 2000000000 ? -1 : sol);

}

Compilation message (stderr)

race.cpp: In function 'void precalc(int, int)':
race.cpp:16:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i = 0 ; i < v[nod].size() ; i++){
                  ~~^~~~~~~~~~~~~~~
race.cpp: In function 'void dfs(int, int, int)':
race.cpp:30:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i = 0 ; i < v[nod].size() ; i++){
                  ~~^~~~~~~~~~~~~~~
race.cpp:39:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (i = 0 ; i < v[nod].size() ; i++){
                  ~~^~~~~~~~~~~~~~~
race.cpp:57:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (i = 0 ; i < v[nod].size() ; i++){
                      ~~^~~~~~~~~~~~~~~
race.cpp:27:32: warning: 'fiu' may be used uninitialized in this function [-Wmaybe-uninitialized]
     int i , vecin , maxi = 0 , fiu , rms;
                                ^~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 22
• Subtask 4: 0 / 57