Description

http://www.lydsy.com/JudgeOnline/upload/zjoi2012.pdf

Solution

維護樹上聯通塊的信息，支持動態加邊刪邊
LCT
總共只有10種顏色，直接建10個LCT，每個LCT維護一種顏色
LCT還是差不多
只是第二個操作比較麻煩，得一個一個顏色地去試

#include<bits/stdc++.h>
#define ll long long
#define db double
#define ld long double
#define lc(x) ch[(x)][0]
#define rc(x) ch[(x)][1]
const int
 
 MAXN=10000+10,MAXC=15;
int n,m,c,k,Val[MAXN],d[MAXC][MAXN];
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);}
struct LCT{
    int ch[MAXN][2],fa[MAXN],rev[MAXN],Mx[MAXN];
    inline void init()
    {
        memset(ch,0
 
,sizeof(ch));
        memset(fa,0,sizeof(fa));
        memset(rev,0,sizeof(rev));
        memset(Mx,0,sizeof(Mx));
    }
    inline bool nroot(int x)
    {
        return lc(fa[x])==x||rc(fa[x])==x;
    }
    inline void reverse(int x)
    {
        std::swap(lc(x),rc(x));
        rev[x]^=1;
    }
    inline
 
 void pushup(int x)
    {
        Mx[x]=Val[x];
        chkmax(Mx[x],Mx[lc(x)]);
        chkmax(Mx[x],Mx[rc(x)]);
    }
    inline void pushdown(int x)
    {
        if(rev[x])
        {
            if(lc(x))reverse(lc(x));
            if(rc(x))reverse(rc(x));
            rev[x]=0;
        }
    }
    inline void rotate(int x)
    {
        int f=fa[x],p=fa[f],c=(rc(f)==x);
        if(nroot(f))ch[p][rc(p)==f]=x;
        fa[ch[f][c]=ch[x][c^1]]=f;
        fa[ch[x][c^1]=f]=x;
        fa[x]=p;
        pushup(f);
        pushup(x);
    }
    inline void splay(int x)
    {
        std::stack<int> s;
        s.push(x);
        for(register int i=x;nroot(i);i=fa[i])s.push(fa[i]);
        while(!s.empty())pushdown(s.top()),s.pop();
        for(register int y=fa[x];nroot(x);rotate(x),y=fa[x])
            if(nroot(y))rotate((lc(y)==x)==(lc(fa[y])==y)?y:x);
        pushup(x);
    }
    inline void access(int x)
    {
        for(register int y=0;x;x=fa[y=x])splay(x),rc(x)=y,pushup(x);
    }
    inline void makeroot(int x)
    {
        access(x);splay(x);reverse(x);
    }
    inline int findroot(int x)
    {
        access(x);splay(x);
        while(lc(x))pushdown(x),x=lc(x);
        splay(x);
        return x;
    }
    inline void split(int x,int y)
    {
        makeroot(x);access(y);splay(y);
    }
    inline void link(int x,int y)
    {
        makeroot(x);
        if(findroot(y)!=x)fa[x]=y;
    }
    inline void cut(int x,int y)
    {
        makeroot(x);
        if(findroot(y)==x&&fa[y]==x&&!lc(y))rc(x)=fa[y]=0,pushup(x);
    }
};
LCT T[MAXC];
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 c='\0')
{
    if(x<0)putchar('-'),x=-x;
    if(x>9)write(x/10);
    putchar(x%10+'0');
    if(c!='\0')putchar(c);
}
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;}
int main()
{
    read(n);read(m);read(c);read(k);
    for(register int i=1;i<=c;++i)T[i].init();
    for(register int i=1;i<=n;++i)read(Val[i]);
    for(register int i=1;i<=m;++i)
    {
        int u,v,w;
        read(u);read(v);read(w);
        w++;
        d[w][u]++;d[w][v]++;
        T[w].link(u,v);
    }
    while(k--)
    {
        int opt;
        read(opt);
        if(opt==0)
        {
            int x,y;
            read(x);read(y);
            Val[x]=y;
            for(register int i=1;i<=c;++i)T[i].access(x),T[i].splay(x),T[i].pushup(x);
        }
        if(opt==1)
        {
            int u,v,w,dn=1;
            read(u);read(v);read(w);
            w++;
            for(register int i=1;i<=c;++i)
                if(T[i].findroot(u)==T[i].findroot(v))
                {
                    T[i].makeroot(u),T[i].access(v),T[i].splay(v);
                    if(T[i].lc(v)!=u||T[i].rc(u))continue;
                    dn=0;
                    if(i==w)puts("Success.");
                    else if(d[w][u]>=2||d[w][v]>=2)puts("Error 1.");
                    else if(T[w].findroot(u)==T[w].findroot(v))puts("Error 2.");
                    else
                    {
                        T[i].cut(u,v);T[w].link(u,v);
                        d[i][u]--;d[i][v]--;
                        d[w][u]++;d[w][v]++;
                        puts("Success.");
                    }
                    break;
                }
            if(dn)puts("No such edge.");
        }
        if(opt==2)
        {
            int c,u,v;
            read(c);read(u);read(v);
            c++;
            if(T[c].findroot(u)!=T[c].findroot(v))puts("-1");
            else T[c].split(u,v),write(T[c].Mx[v],'\n');
        }
    }
    return 0;
}

【刷題】BZOJ 2816 [ZJOI2012]網絡