제출 #994541

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
994541		aaaaaarroz	봉쇄 시간 (IOI23_closing)	C++17	0 / 100	847 ms	2097152 KiB

closing

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
vector<vector<pair<ll,ll>>>graph;
vector<bool> vis;
void dfs1(vector<ll> &dist, ll x, ll d){
    vis[x] = true;
    dist[x] = d;
    for (auto [y, w] : graph[x]){
        if (!vis[y]){
            dfs1(dist, y, d + w);
        }
    }
}
void dfs2(vector<pair<ll,ll>>dist, ll x, ll d){
    vis[x] = true;
    dist[x].first= d;
    for (auto [y, w] : graph[x]){
        if (!vis[y]){
            dfs2(dist, y, d + w);
        }
    }
}
ll max_score(int N, int X, int Y, ll K, vector<int> U, vector<int> V, vector<int> W){
	graph.assign(N,vector<pair<ll,ll>>());
	for(ll i=0;i<(N-1);i++){
		graph[U[i]].push_back({V[i],W[i]});
		graph[V[i]].push_back({U[i],W[i]});
	}
	vis.assign(N,false);
	vector<ll>distX(N);
	dfs1(distX,X,0);
	vis.assign(N,false);
	vector<ll>distY(N);
	dfs1(distY,Y,0);
	vis.assign(N,false);
	vector<pair<ll,ll>>orden;
	for(ll i=0;i<N;i++){
		pair<ll,ll>par;
		par.first=0;
		par.second=i;
		orden.push_back(par);
	}
	dfs2(orden,max_element(distX.begin(),distX.end())-distX.begin(),0);
	sort(orden.begin(),orden.end());
	ll pos_x;
	ll pos_y;
	for(ll i=0;i<N;i++){
		if(orden[i].second==X){
			pos_x=i;
		}
		else if(orden[i].second==Y){
			pos_y=i;
		}
	}
	pos_x++;
	pos_y++;
	vector<ll>prefix1(N+1,0);
	for(ll i=0;i<N;i++){
		prefix1[i+1]=prefix1[i]+distX[orden[i].second];
	}
	vector<ll>prefix2(N+1,0);
	for(ll i=0;i<N;i++){
		prefix2[i+1]=prefix2[i]+distY[orden[i].second];
	}
	vector<ll>prefixMax(N+1,0);
	for(ll i=0;i<N;i++){
		prefixMax[i+1]=prefixMax[i]+min(distY[orden[i].second],distX[orden[i].second]);
	}
	ll ans=0;
	for(ll i=0;i<pos_x;i++){
		for(ll j=pos_x;j<=N;j++){
			for(ll k=0;k<pos_y;k++){
				for(ll l=pos_y;l<=N;l++){
					ll suma=(prefix1[j]-prefix1[i]+prefix2[l]-prefix2[k]);
					if(k>=i&&l<=j){
						suma-=(prefixMax[l]-prefixMax[k]);
					}
					else if(i>=k&&j<=l){
						suma-=(prefixMax[j]-prefixMax[i]);
					}
					else if(k>=i&&k<=j){
						suma-=(prefixMax[j]-prefixMax[l]);
					}
					else if(i>=k&&i<=l){
						suma-=(prefixMax[l]-prefixMax[i]);
					}
					if(suma<=K){
						ans=max((j-i+l-k),ans);
					}
				}
			}
		}
	}
	return ans;
}

컴파일 시 표준 에러 (stderr) 메시지

closing.cpp: In function 'll max_score(int, int, int, ll, std::vector<int>, std::vector<int>, std::vector<int>)':
closing.cpp:56:7: warning: 'pos_x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   56 |  pos_x++;
      |  ~~~~~^~
closing.cpp:57:7: warning: 'pos_y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   57 |  pos_y++;
      |  ~~~~~^~

• Subtask 0: 0 / 0
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• Subtask 2: 0 / 9
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• Subtask 9: 0 / 17