답안 #115752

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
115752	2019-06-08T20:42:26 Z	YazanZk	경주 (Race) (IOI11_race)	C++14	컴파일 오류	0 ms	0 KB

race

#include <bits/stdc++.h>
typedef long long ll ;
using namespace std;
const int N = 200005;

vector < pair < int , int > > G[N];
int sub[N] , par[N];
bool blocked[N];

int n , k ;

void get_size(int u, int p){

    par[u] = p ;
    sub[u] = 1 ;

    for(auto ch : G[u]){
          int v = ch.first;
          if(v == p || blocked[v]) continue ;
          get_size(v , u);
          sub[u] += sub[v];
    }
}

set < pair < int , int > > se;

int dfs(int u , int p , ll w , int d){

    if(w > k) return n ;

    int ret = n ;

    auto it = *se.lower_bound({k - w , 0});
    if(it.first == k - w)
          ret = d + it.second ;

    for(auto ch : G[u]){
          int v = ch.first , ww = ch.second ;
          if(v == p || blocked[v]) continue ;
          ret = min(ret , dfs(v , u , w + ww , d + 1));
    }

    return ret ;
}

void update(int u , int p , ll w , int d){

     se.insert({w , d});

     for(auto ch : G[u]){
          int v = ch.first , ww = ch.second ;
          if(v == p || blocked[v]) continue ;
          update(v , u , w + ww , d + 1);
     }
}

int solve(int u){

    se.clear() ;

    int ret = n ;

    for(auto ch : G[u]){
          int v = ch.first , w = ch.second ;
          if(blocked[v]) continue ;
          ret = min(ret , dfs(v , u , w , 1));
          update(v , u , w , 1);
    }

    return ret;
}

int get_centroid(int src){

    get_size(src , src);

    queue < int > Q ;
    Q.push(src);

    int centroid = src , best = sub[src];

    while(!Q.empty()){
          int u = Q.front();
          Q.pop();

          int size = sub[src] - sub[u];
          for(auto ch : G[u]){
              int v = ch.first;
              if(v == par[u] || blocked[v]) continue ;
              Q.push(v);
              size = max(size , sub[v]);
          }

          if(best > size){
               best = size ;
               centroid = u ;
          }
    }

    blocked[centroid] = true ;

    int ret = solve(centroid);

    for(auto ch : G[centroid]){
          int v = ch.first;
          if(blocked[v]) continue ;
          ret = min(ret , get_centroid(v));
    }

    return ret;
}


int main() {
    ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);

    cin >> n >> k ;

    vector < pair < int , int > > ve ;

    for(int i = 0 ; i < n - 1 ; i++){
          int u , v ;
          cin >> u >> v ;
          ve.push_back({u , v});
    }

    for(auto i : ve){
          int x ; cin >> x ;
          G[i.first].push_back({i.second , x});
          G[i.second].push_back({i.first , x});
    }

    int ans = get_centroid(0);

    if(ans == n) ans = -1 ;

    cout << ans << endl ;

    return 0;
}

Compilation message

/tmp/cc6vKUAx.o: In function `main':
race.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccJZ72eB.o:grader.cpp:(.text.startup+0x0): first defined here
/tmp/ccJZ72eB.o: In function `main':
grader.cpp:(.text.startup+0x20): undefined reference to `best_path(int, int, int (*) [2], int*)'
collect2: error: ld returned 1 exit status