【刷题】BZOJ 5415 [Noi2018]归程

www.lydsy.com/JudgeOnline/upload/noi2018day1.pdf

Solution

考试的时候打的可持久化并查集，没调出来QAQ

后面知道了kruskal重构树这个东西，感觉好简单啊

这道题就建出kruskal重构树后，对于两个点找到它们的LCA，其子树min就是答案

#include<bits/stdc++.h>

#define ui unsigned int

#define ll long long

#define db double

#define ld long double

#define ull unsigned long long

const int MAXN=200000+10,MAXM=400000+10,inf=0x3f3f3f3f;

int T,n,m,e,beg[MAXN],nex[MAXM<<1],to[MAXM<<1],w[MAXM<<1],wt[MAXN<<1],Mn[MAXN<<1],cnt,d[MAXN],fa[MAXN<<1],Jie[20][MAXN<<1];

ll lastans;

struct node{

	int u,v,l,a;

	inline bool operator < (const node &A) const {

		return a>A.a;

	}

};

node side[MAXM];

struct cmp{

	inline bool operator () (int a,int b) const {

		return d[a]>d[b];

	}

};

std::priority_queue<int,std::vector<int>,cmp> q;

template<typename T> inline void read(T &x)

{

	T data=0,w=1;

	char ch=0;

	while(ch!='-'&&(ch<'0'||ch>'9'))ch=getchar();

	if(ch=='-')w=-1,ch=getchar();

	while(ch>='0'&&ch<='9')data=((T)data<<3)+((T)data<<1)+(ch^'0'),ch=getchar();

	x=data*w;

}

template<typename T> inline void write(T x,char ch='\0')

{

	if(x<0)putchar('-'),x=-x;

	if(x>9)write(x/10);

	putchar(x%10+'0');

	if(ch!='\0')putchar(ch);

}

template<typename T> inline void chkmin(T &x,T y){x=(y<x?y:x);}

template<typename T> inline void chkmax(T &x,T y){x=(y>x?y:x);}

template<typename T> inline T min(T x,T y){return x<y?x:y;}

template<typename T> inline T max(T x,T y){return x>y?x:y;}

inline void insert(int x,int y,int z)

{

	to[++e]=y;

	nex[e]=beg[x];

	beg[x]=e;

	w[e]=z;

}

inline void dijkstra()

{

	for(register int i=1;i<=n;++i)d[i]=inf;

	d[1]=0;

	q.push(1);

	while(!q.empty())

	{

		int x=q.top();

		q.pop();

		for(register int i=beg[x];i;i=nex[i])

			if(d[to[i]]>d[x]+w[i])d[to[i]]=d[x]+w[i],q.push(to[i]);

	}

}

inline int found(int x)

{

	if(x!=fa[x])fa[x]=found(fa[x]);

	return fa[x];

}

inline void init()

{

	dijkstra();

	cnt=n;

	std::sort(side+1,side+m+1);

	for(register int i=1;i<=n;++i)Mn[i]=d[i];

	for(register int i=1;i<=n+n-1;++i)fa[i]=i,wt[i]=inf;

	for(register int i=1,u,v;i<=m;++i)

	{

		u=found(side[i].u),v=found(side[i].v);

		if(u==v)continue;

		else

		{

			cnt++;

			Mn[cnt]=min(Mn[u],Mn[v]);

			wt[cnt]=side[i].a;

			fa[u]=fa[v]=cnt;

			Jie[0][u]=Jie[0][v]=cnt;

		}

	}

	for(register int j=1;j<=19;++j)

		for(register int i=1;i<=cnt;++i)Jie[j][i]=Jie[j-1][Jie[j-1][i]];

}

inline int Get(int x,int a)

{

	for(register int i=19;i>=0;--i)

		if(wt[Jie[i][x]]>a)x=Jie[i][x];

	return x;

}

int main()

{

	read(T);

	while(T--)

	{

		e=0;lastans=0;

		read(n);read(m);

		for(register int i=1;i<=n;++i)beg[i]=0;

		for(register int i=1,u,v,l,a;i<=m;++i)

		{

			read(u);read(v);read(l);read(a);

			side[i]=(node){u,v,l,a};

			insert(u,v,l);insert(v,u,l);

		}

		init();

		ll Q,K,S;

		read(Q);read(K);read(S);

		while(Q--)

		{

			ll v0,p0,v,p;read(v0);read(p0);

			v=(v0+1ll*K*lastans-1)%n+1;

			p=(p0+1ll*K*lastans)%(S+1);

			write(lastans=Mn[Get(v,p)],'\n');

		}

	}

	return 0;

}