【BZOJ 2243】染色 - 树链剖分+线段树

来源：互联网发布：js 0开头数字转字符串编辑：程序博客网时间：2024/06/10 06:07
#include <cstdio>#include <cstring>#include <cstdlib>using namespace std;const int N=100001;int n,m,color[N];   //Basicstruct G{    int v,nxt;}map[N+N];int hd[N],tt;   //Graphint son[N],dep[N],pre[N],size[N];int tid[N],top[N],num;  //Chainstruct T{    int l,r;    int lc,rc,tag;    int cnt;}tr[N<<2];    //Segment Treeinline int read(void){    int s=0,f=1; char c=getchar();    for (;c<'0'||c>'9';c=getchar()) if (c=='-') f=-1;    for (;'0'<=c&&c<='9';c=getchar()) s=(s<<1)+(s<<3)+c-'0';    return s*f;}inline void ins(int u,int v){    map[++tt].v=v;    map[tt].nxt=hd[u];    hd[u]=tt;}void find(int now,int ht){    dep[now]=ht,size[now]=1;    for (int k=hd[now];k;k=map[k].nxt)        if (!size[map[k].v])        {            find(map[k].v,ht+1);            size[now]+=size[map[k].v];            pre[map[k].v]=now;            if (!son[now]||size[son[now]]<size[map[k].v]) son[now]=map[k].v;        }}void cut(int now,int anc){    top[now]=anc,tid[now]=++num;    if (son[now]) cut(son[now],anc);    for (int k=hd[now];k;k=map[k].nxt)        if (!tid[map[k].v]) cut(map[k].v,map[k].v);}inline void clear(int now){    if (tr[now].tag==-1) return;    tr[now<<1].tag=tr[now<<1|1].tag=tr[now].tag;    tr[now<<1].lc=tr[now<<1].rc=tr[now].tag;    tr[now<<1|1].lc=tr[now<<1|1].rc=tr[now].tag;    tr[now<<1].cnt=tr[now<<1|1].cnt=1;    tr[now].tag=-1;}void build(int now,int l,int r){    tr[now].l=l;    tr[now].r=r;    tr[now].tag=-1;    if (l^r)    {        int mid=l+r>>1;        build(now<<1,l,mid);        build(now<<1|1,mid+1,r);    }}void ins(int now,int l,int r,int c){    if (l<=tr[now].l&&tr[now].r<=r)    {        tr[now].tag=tr[now].lc=tr[now].rc=c;        tr[now].cnt=1;        return;    }    clear(now);    int mid=tr[now].l+tr[now].r>>1;    if (l<=mid) ins(now<<1,l,r,c);    if (mid<r) ins(now<<1|1,l,r,c);    tr[now].lc=tr[now<<1].lc;    tr[now].rc=tr[now<<1|1].rc;    tr[now].cnt=tr[now<<1].cnt+tr[now<<1|1].cnt-(tr[now<<1].rc==tr[now<<1|1].lc);}void init(void){    n=read(),m=read();    for (int i=1;i<=n;i++) color[i]=read();    int u,v;    for (int i=1;i<n;i++)    {        u=read(),v=read();        ins(u,v),ins(v,u);    }    find(1,1);    cut(1,1);    build(1,1,n);    for (int i=1;i<=n;i++) ins(1,tid[i],tid[i],color[i]);}inline int LCA(int x,int y){    for (;top[x]^top[y];)        if (dep[top[x]]>dep[top[y]])            x=pre[top[x]];        else y=pre[top[y]];    return dep[x]<dep[y]?x:y;}int query(int now,int l,int r){    if (l<=tr[now].l&&tr[now].r<=r) return tr[now].cnt;    clear(now);    int mid=tr[now].l+tr[now].r>>1,sum=0;    if (l<=mid) sum+=query(now<<1,l,r);    if (mid<r) sum+=query(now<<1|1,l,r);    if (l<=mid&&mid<r) sum-=tr[now<<1].rc==tr[now<<1|1].lc;    return sum;}int findcolor(int now,int loc){    if (tr[now].l==tr[now].r) return tr[now].tag;    clear(now);    int mid=tr[now].l+tr[now].r>>1;    return findcolor(now<<1|(loc<=mid?0:1),loc);}void work(void){    char c; int x,y,z,p,res,uc,dc;    for (int i=1;i<=m;i++)    {        scanf("\n%c",&c);        if (c=='C')        {            x=read(),y=read(),z=read(),p=LCA(x,y);            for (;top[x]^top[p];x=pre[top[x]]) ins(1,tid[top[x]],tid[x],z);            for (;top[y]^top[p];y=pre[top[y]]) ins(1,tid[top[y]],tid[y],z);            ins(1,tid[p],x^p?tid[x]:tid[y],z);        }        else        {            x=read(),y=read(),p=LCA(x,y);            uc=dc=-1,res=0;            for (;top[x]^top[p];x=pre[top[x]])            {                if (uc^-1)                 {                    dc=findcolor(1,tid[x]);                    res-=uc==dc;                }                res+=query(1,tid[top[x]],tid[x]);                uc=findcolor(1,tid[top[x]]);            }            dc=findcolor(1,tid[x]);            res-=uc==dc;            uc=dc=-1;            for (;top[y]^top[p];y=pre[top[y]])            {                if (uc^-1)                {                    dc=findcolor(1,tid[y]);                    res-=uc==dc;                }                res+=query(1,tid[top[y]],tid[y]);                uc=findcolor(1,tid[top[y]]);            }            dc=findcolor(1,tid[y]);            res-=uc==dc;            res+=query(1,tid[p],x^p?tid[x]:tid[y]);            printf("%d\n",res);        }    }}int main(void){       init();    work();    return 0;}
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