【刷题】UOJ #274 【清华集训2016】温暖会指引我们前行

#include<bits/stdc++.h>
#define ll long long
#define db double
#define ld long double
const int MAXN=100000+10,MAXM=300000+10,inf=0x3f3f3f3f;
int n,m,fa[MAXN];
struct edge{
    int u,v,t,l;
};
edge side[MAXM];
#define lc(x) ch[(x)][0]
#define rc(x) ch[(x)][1]
struct LCT{
    int ch[MAXN+MAXM][2],fa[MAXN+MAXM],id[MAXN+MAXM],val[MAXN+MAXM],Mn[MAXN+MAXM],rev[MAXN+MAXM],stack[MAXN+MAXM],cnt,sum[MAXN+MAXM],was[MAXN+MAXM];
    inline void init()
    {
        memset(ch,0,sizeof(ch));
        memset(fa,0,sizeof(fa));
        memset(id,0,sizeof(id));
        memset(Mn,inf,sizeof(Mn));
        memset(val,inf,sizeof(val));
        memset(sum,0,sizeof(sum));
        memset(was,0,sizeof(was));
        memset(rev,0,sizeof(rev));
    }
    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)
    {
        sum[x]=sum[lc(x)]+sum[rc(x)]+was[x];
        Mn[x]=val[x],id[x]=x;
        if(Mn[lc(x)]<Mn[x])Mn[x]=Mn[lc(x)],id[x]=id[lc(x)];
        if(Mn[rc(x)]<Mn[x])Mn[x]=Mn[rc(x)],id[x]=id[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)
    {
        cnt=0;
        stack[++cnt]=x;
        for(register int i=x;nroot(i);i=fa[i])stack[++cnt]=fa[i];
        while(cnt)pushdown(stack[cnt--]);
        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 int findroot(int x)
    {
        access(x);splay(x);
        while(lc(x))pushdown(x),x=lc(x);
        splay(x);
        return x;
    }
    inline void makeroot(int x)
    {
        access(x);splay(x);reverse(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&&!rc(y))fa[y]=lc(x)=0,pushup(x);
    }
};
LCT T;
#undef lc
#undef rc
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 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 int found(int x)
{
    if(fa[x]!=x)fa[x]=found(fa[x]);
    return fa[x];
}
int main()
{
    read(n);read(m);
    for(register int i=1;i<=n;++i)fa[i]=i;
    T.init();
    while(m--)
    {
        char opt[10];
        scanf("%s",opt);
        if(opt[0]=='f')
        {
            int id,u,v,t,l;
            read(id);read(u);read(v);read(t);read(l);
            if(u>v)std::swap(u,v);
            id++;u++;v++;
            side[id].u=u;side[id].v=v;
            side[id].t=t;side[id].l=l;
            int x=found(u),y=found(v),sn=n+id;
            if(x!=y)
            {
                fa[x]=y;
                T.val[sn]=t;T.was[sn]=l;
                T.link(sn,u);T.link(sn,v);
            }
            else
            {
                T.split(u,v);
                int so=T.id[v];
                if(t>T.Mn[v])
                {
                    T.val[sn]=t;T.was[sn]=l;
                    T.cut(so,side[so-n].u);T.cut(so,side[so-n].v);
                    T.link(sn,u);T.link(sn,v);
                }
            }
        }
        if(opt[0]=='m')
        {
            int u,v;
            read(u);read(v);
            if(u>v)std::swap(u,v);
            u++;v++;
            if(found(u)!=found(v))puts("-1");
            else T.split(u,v),write(T.sum[v],'\n');
        }
        if(opt[0]=='c')
        {
            int id,l;
            read(id);read(l);
            id++;
            T.splay(n+id);T.was[n+id]=l;T.pushup(n+id);
        }
    }
    return 0;
}