제출 #501641

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
501641		mars4	Valley (BOI19_valley)	C++17	100 / 100	300 ms	59372 KiB

valley

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp> 

using namespace std;
using namespace __gnu_pbds; 

#define ff              first
#define ss              second
#define ll              int64_t
#define ld              long double
#define nl              cout<<"\n"
#define all(v)          v.begin(),v.end()
#define mset(a,v)       memset((a),(v),sizeof(a))
#define forn(i,a,b)     for(int64_t i=int64_t(a);i<int64_t(b);++i)
#define forb(i,a,b)     for(int64_t i=int64_t(a);i>=int64_t(b);--i)
#define fastio()        ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);

#define mod         1'000'000'007
#define mod2        998'244'353 
#define inf         1'000'000'000'000'007
#define pi          3.14159265358979323846

template<class key,class cmp=std::less<key>>
using ordered_set=tree<key,null_type,cmp,rb_tree_tag,tree_order_statistics_node_update>;

template<class L,class R> ostream& operator<<(ostream& out,pair<L,R> &p)        {return out<<"("<<p.ff<<", "<<p.ss<<")";}
template<class T> ostream& operator<<(ostream& out,vector<T> &v)                {out<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())out<<", ";out<<*it;}return out<<"]";}
template<class T> ostream& operator<<(ostream& out,deque<T> &v)                 {out<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())out<<", ";out<<*it;}return out<<"]";}
template<class T> ostream& operator<<(ostream& out,set<T> &s)                   {out<<"{";for(auto it=s.begin();it!=s.end();++it){if(it!=s.begin())out<<", ";out<<*it;}return out<<"}";}
template<class L,class R> ostream& operator<<(ostream& out,map<L,R> &m)         {out<<"{";for(auto it=m.begin();it!=m.end();++it){if(it!=m.begin())out<<", ";out<<*it;}return out<<"}";}

void dbg_out() {cerr<<"]\n";}
template<typename Head,typename... Tail> 
void dbg_out(Head H,Tail... T) {cerr<<H;if(sizeof...(Tail))cerr<<", ";dbg_out(T...);}
#ifdef LOCAL
	#define dbg(...) cerr<<"["<<#__VA_ARGS__<<"] = [",dbg_out(__VA_ARGS__)
#else
	#define dbg(...)
#endif

//---------------------------------mars4---------------------------------

vector<vector<pair<ll,ll>>> v;
vector<ll> st;
vector<ll> ed;
vector<ll> sval;
vector<ll> dist;
vector<ll> depth;
vector<bool> shop;
vector<vector<ll>> dp;
vector<vector<ll>> val;
ll timer;
ll logN=18;

void dfs(ll cur,ll prev,ll len,ll level)
{
	timer++;
	st[cur]=timer;
	dist[cur]=len;
	depth[cur]=level;
	sval[cur]=shop[cur]?dist[cur]:inf;
	for(auto [i,w]:v[cur])
	{
		if(i!=prev)
		{
			dfs(i,cur,len+w,level+1);
			sval[cur]=min(sval[cur],sval[i]);
		}
	}
	dp[cur][0]=prev;
	val[cur][0]=sval[cur]==inf?inf:sval[cur]-2*dist[cur];
	ed[cur]=timer;
}

int main()
{
	fastio();
	ll z,n,m,t,k,i,j,l,d,h,r;
	ll s,root;
	cin>>n>>s>>m>>root;
	root--;
	v=vector<vector<pair<ll,ll>>>(n);
	dp=vector<vector<ll>>(n,vector<ll>(logN));
	val=vector<vector<ll>>(n,vector<ll>(logN));
	st=vector<ll>(n);
	ed=vector<ll>(n);
	sval=vector<ll>(n);
	dist=vector<ll>(n);
	depth=vector<ll>(n);
	shop=vector<bool>(n);
	timer=-1;
	vector<pair<ll,ll>> edges(n-1);
	forn(i,0,n-1)
	{
		cin>>l>>r>>d;
		l--,r--;
		v[l].push_back({r,d});
		v[r].push_back({l,d});
		edges[i]={l,r};
	}
	forn(i,0,s)
	{
		cin>>r;
		shop[r-1]=true;
	}
	dfs(root,root,0,0);
	forn(j,1,logN)
	{
		forn(i,0,n)
		{
			dp[i][j]=dp[dp[i][j-1]][j-1];
			val[i][j]=min(val[i][j-1],val[dp[i][j-1]][j-1]);
		}
	}
	while(m--)
	{
		ll ind,cur;
		cin>>ind>>cur;
		ind--,cur--;
		auto [l,r]=edges[ind];
		if(dist[l]<dist[r])
		{
			swap(l,r);
		}
		if(st[l]<=st[cur] and ed[l]>=ed[cur])
		{
			ll mval=val[l][0];
			ll diff=depth[cur]-depth[l];
			ll icur=cur;
			forb(k,logN-1,0)
			{
				if(diff&(1ll<<k))
				{
					mval=min(mval,val[cur][k]);
					cur=dp[cur][k];
				}
			}
			mval+=dist[icur];
			if(mval>=inf)
			{
				cout<<"oo\n";
			}
			else
			{
				cout<<mval<<"\n";
			}
		}
		else
		{
			cout<<"escaped\n";
		}
	}
	cerr<<"\nTime elapsed: "<<1000*clock()/CLOCKS_PER_SEC<<"ms\n";
	return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

valley.cpp: In function 'int main()':
valley.cpp:79:5: warning: unused variable 'z' [-Wunused-variable]
   79 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |     ^
valley.cpp:79:11: warning: unused variable 't' [-Wunused-variable]
   79 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |           ^
valley.cpp:79:13: warning: unused variable 'k' [-Wunused-variable]
   79 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |             ^
valley.cpp:79:15: warning: unused variable 'i' [-Wunused-variable]
   79 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |               ^
valley.cpp:79:17: warning: unused variable 'j' [-Wunused-variable]
   79 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |                 ^
valley.cpp:79:23: warning: unused variable 'h' [-Wunused-variable]
   79 |  ll z,n,m,t,k,i,j,l,d,h,r;
      |                       ^

• Subtask 1: 9 / 9
• Subtask 2: 27 / 27
• Subtask 3: 23 / 23
• Subtask 4: 41 / 41