제출 #951078

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
951078		batsukh2006	경주 (Race) (IOI11_race)	C++17	100 / 100	711 ms	40208 KiB

race

#include "race.h"
#include<iostream>
#include<stdio.h>
#include<math.h>
#include<map>
#include<string>
#include<algorithm>
#include<vector>
#include<string.h>
#include<utility>
#include<set>
#include<cmath>
#include<queue>
#include<deque>
#include<functional>
#include<stack>
#include<limits.h>
#include<iomanip>
#include<unordered_map> 
#include<numeric>
#include<tuple>
#include<bitset>
using namespace std;
 
#define endl '\n'
#define ff first
#define ss second
// #define int long long
#define MOD 1000000007
static const bool __boost = [](){
    cin.tie(0);
    cout.tie(0);
    return ios::sync_with_stdio(0);
}();
int n,k;
int ans=1e9;
map<int,int> mp;
const int mxN=2e5+1;
const int mxM=1e6+1;
vector<bool> vis(mxN);
vector<pair<int,int> > v[mxN];
vector<int> sub(mxN),cnt(mxM);
void cal(int a, int p, int d, int w){
    if(mp.count(k-w)) ans=min(ans,d+mp[k-w]);
    for(auto node: v[a]){
        if(node.ff!=p&&!vis[node.ff]){
            cal(node.ff,a,d+1,w+node.ss);
        }
    }
}
void up(int a, int p, int d, int w){
    if(w<=k){
        if(mp.count(w)) mp[w]=min(mp[w],d);
        else mp[w]=d;
    }else{
        return;
    }
    for(auto node: v[a]){
        if(node.ff!=p&&!vis[node.ff]){
            up(node.ff,a,d+1,w+node.ss);
        }
    }
}
int dfs(int a, int p){
    sub[a]=1;
    for(auto node: v[a]){
        if(node.ff!=p&&!vis[node.ff]){
            sub[a]+=dfs(node.ff,a);
        }
    }
    return sub[a];
}
int find(int a, int p, int s){
    for(auto node: v[a]){
        if(node.ff!=p&&!vis[node.ff]&&sub[node.ff]>s/2){
            return find(node.ff,a,s);
        }
    }
    return a;
}
void build(int a, int p){
    int cd=find(a,p,dfs(a,p));
    vis[cd]=1;
    mp[0]=0;
    for(auto node: v[cd]){
        if(!vis[node.ff]){
            cal(node.ff,cd,1,node.ss);
            up(node.ff,cd,1,node.ss);
        }
    }
    for(auto x: mp) cnt[x.ff]=1e9;
    mp.clear();
    for(auto node: v[cd]){
        if(!vis[node.ff]) build(node.ff,cd);
    }
}
int best_path(int N, int K, int H[][2], int L[]){
    __boost;
    n=N;
    k=K;
    for(int i=0; i<n-1; i++){
        v[H[i][0]].push_back({H[i][1],L[i]});
        v[H[i][1]].push_back({H[i][0],L[i]});
    }
    build(1,-1);
    if(ans==1e9) return -1;
    return ans;
}
// signed main(){
//     // freopen("file.in", "r", stdin);
//     // freopen("file.out", "w", stdout);
    
    
//     int T=1;
//     // cin>>T;
//     while(T--){
//         int N,K; cin>>N>>K;
//         int H[N][2],L[N];
//         for(int i=0; i<N-1; i++) cin>>H[i][0]>>H[i][1];
//         for(int i=0; i<N-1; i++) cin>>L[i];
//         cout<<best_path(N,K,H,L);
//     }
//     return 0;
// }

컴파일 시 표준 에러 (stderr) 메시지

race.cpp: In function 'int best_path(int, int, int (*)[2], int*)':
race.cpp:98:5: warning: statement has no effect [-Wunused-value]
   98 |     __boost;
      |     ^~~~~~~

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