【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;
}