- Description
- http://www.lydsy.com/JudgeOnline/upload/zjoi2012.pdf
- Solution
维护树上联通块的信息, 支持动态加边删边
LCT
总共只有 10 种颜色, 直接建 10 个 LCT, 每个 LCT 维护一种颜色
LCT 还是差不多
只是第二个操作比较麻烦, 得一个一个颜色地去试
- #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;
- }
来源: http://www.bubuko.com/infodetail-2546507.html