제출 #126475

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
126475		TadijaSebez	Designated Cities (JOI19_designated_cities)	C++11	100 / 100	641 ms	50864 KiB

designated_cities

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
const int N=200050;
vector<pair<int,int>> E[N];
ll sum[N],all_up;
int up[N],down[N];
ll dep[N];
int lid[N],rid[N],tid,nod[N],par[N],my[N],rt,n;
ll mxd[N],sol[N];
void DFS(int u, int p)
{
	for(auto e:E[u])
	{
		int v=e.first,w=e.second;
		if(v==p) up[u]=w,all_up+=w;
	}
	if(p) sum[u]=sum[p]+down[u]-up[u];
	mxd[u]=0;
	for(auto e:E[u])
	{
		int v=e.first,w=e.second;
		if(v!=p)
		{
			down[v]=w;
			dep[v]=dep[u]+w;
			DFS(v,u);
			mxd[u]=max(mxd[u],mxd[v]+w);
		}
	}
}
void Solve(int u, int p, ll hi)
{
	ll fir=0,sec=0;
	int t=-1;
	sol[u]=max(hi,mxd[u])+sum[u];
	for(auto e:E[u]) if(e.first!=p)
	{
		int v=e.first,w=e.second;
		if(fir<mxd[v]+w) sec=fir,fir=mxd[v]+w,t=v;
		else if(sec<mxd[v]+w) sec=mxd[v]+w;
	}
	for(auto e:E[u]) if(e.first!=p)
	{
		int v=e.first,w=e.second;
		ll best=hi;
		if(t==v) best=max(best,sec);
		else best=max(best,fir);
		Solve(v,u,best+up[v]);
	}
}
void DFS2(int u, int p)
{
	lid[u]=++tid;
	nod[tid]=u;
	par[u]=p;
	my[u]=u;
	for(auto e:E[u]) if(e.first!=p)
	{
		int v=e.first;
		dep[v]=dep[u]+e.second;
		DFS2(v,u);
		if(dep[my[u]]<dep[my[v]]) my[u]=my[v];
	}
	rid[u]=tid;
}
const int M=2*N;
int ls[M],rs[M],tsz,root,id[M];
ll mx[M],lzy[M];
void Build(int &c, int ss, int se)
{
	c=++tsz;
	if(ss==se){ mx[c]=dep[nod[ss]];id[c]=nod[ss];return;}
	int mid=ss+se>>1;
	Build(ls[c],ss,mid);
	Build(rs[c],mid+1,se);
	mx[c]=max(mx[ls[c]],mx[rs[c]]);
	if(mx[c]==mx[ls[c]]) id[c]=id[ls[c]];
	else id[c]=id[rs[c]];
	//printf("%i %lld %i\n",c,mx[c],id[c]);
}
void Add(int c, int ss, int se, int qs, int qe, ll x)
{
	if(qs>qe || qs>se || ss>qe) return;
	if(qs<=ss && qe>=se){ mx[c]+=x;lzy[c]+=x;return;}
	int mid=ss+se>>1;
	Add(ls[c],ss,mid,qs,qe,x);
	Add(rs[c],mid+1,se,qs,qe,x);
	mx[c]=max(mx[ls[c]],mx[rs[c]]);
	if(mx[c]==mx[ls[c]]) id[c]=id[ls[c]];
	else id[c]=id[rs[c]];
	mx[c]+=lzy[c];
}
bool was[N];
ll ans[N],cur;
void Add(int x)
{
	for(;!was[x];x=par[x])
	{
		was[x]=1;
		Add(root,1,n,lid[x],rid[x],-dep[x]+dep[par[x]]);
		cur+=dep[x]-dep[par[x]];
	}
}
int main()
{
	int q,u,v,c,d;
	scanf("%i",&n);
	ll z=0;
	for(int i=1;i<n;i++)
	{
		scanf("%i %i %i %i",&u,&v,&c,&d);
		E[u].pb({v,c});
		E[v].pb({u,d});
		z+=c;
		z+=d;
	}
	DFS(1,0);
	rt=1;
	for(int i=1;i<=n;i++)
	{
		sum[i]+=all_up;
		if(sum[i]>sum[rt]) rt=i;
	}
	ans[1]=sum[rt];
	Solve(1,0,0);
	for(int i=1;i<=n;i++) if(sol[i]>sol[rt]) rt=i;
	//ans[2]=sol[rt];
	for(int i=1;i<=n;i++) dep[i]=0;
	DFS2(rt,0);
	Build(root,1,n);
	cur=sum[rt];
	//printf("cur:%lld\n",cur);
	/*int fir=0,sec=0;
	for(auto e:E[rt])
	{
		v=e.first;
		if(dep[my[v]]>dep[fir]) sec=fir,fir=my[v];
		else if(dep[my[v]]>dep[sec]) sec=my[v];
	}
	Add(fir);
	if(sec) Add(sec);*/
	was[rt]=1;
	for(int i=2;i<=n;i++)
	{
		//printf("%i: %i\n",i,id[root]);
		if(id[root]!=rt) Add(id[root]);
		ans[i]=max(ans[i],cur);
	}
	scanf("%i",&q);
	while(q--)
	{
		int x;
		scanf("%i",&x);
		printf("%lld\n",z-ans[x]);
	}
	return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

designated_cities.cpp: In function 'void Solve(int, int, long long int)':
designated_cities.cpp:46:17: warning: unused variable 'w' [-Wunused-variable]
   int v=e.first,w=e.second;
                 ^
designated_cities.cpp: In function 'void Build(int&, int, int)':
designated_cities.cpp:75:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=ss+se>>1;
          ~~^~~
designated_cities.cpp: In function 'void Add(int, int, int, int, int, long long int)':
designated_cities.cpp:87:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=ss+se>>1;
          ~~^~~
designated_cities.cpp: In function 'int main()':
designated_cities.cpp:109:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i",&n);
  ~~~~~^~~~~~~~~
designated_cities.cpp:113:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%i %i %i %i",&u,&v,&c,&d);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
designated_cities.cpp:151:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i",&q);
  ~~~~~^~~~~~~~~
designated_cities.cpp:155:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%i",&x);
   ~~~~~^~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 9 / 9
• Subtask 4: 17 / 17
• Subtask 5: 17 / 17
• Subtask 6: 44 / 44