bzoj2594: [Wc2006]水管局长数据加强版

离线处理后不难发现就是一个LCT询问两点间最大值最小值之类的，然后就上模板

#include <iostream>#include <algorithm>#include <cstdio>#include <cstring>#include <cmath>using namespace std;int getint(){    char ch = getchar();    for ( ; ch > '9' || ch < '0'; ch = getchar());    int tmp = 0;    for ( ; '0' <= ch && ch <= '9'; ch = getchar())      tmp = tmp * 10 + ch-'0';    return tmp;}int n,m,Q,top;int f[1500005];int fa[1500005],tr[1500005][2],s[1500005];int mx[1500005],val[1500005];bool rev[1500005];struct edge{int u,v,w,id;bool d;}e[1000005];struct que{int f,x,y,ans,id;}q[100005];bool cmp(edge a,edge b){    return a.w<b.w;}bool cmp2(edge a,edge b){    return a.id<b.id;}bool operator<(edge a,edge b){    return a.u<b.u||(a.u==b.u&&a.v<b.v);}int getf(int x){return x==f[x]?x:f[x]=getf(f[x]);}bool isroot(int x){    return (tr[fa[x]][0]!=x)&&(tr[fa[x]][1]!=x);}void pushup(int x){    int l=tr[x][0],r=tr[x][1];    mx[x]=x;    if(val[mx[l]]>val[mx[x]])mx[x]=mx[l];    if(val[mx[r]]>val[mx[x]])mx[x]=mx[r];}void rotate(int x){    int y=fa[x],z=fa[y],l,r;    if(tr[y][0]==x)l=0;else l=1;r=l^1;    if(!isroot(y))    {        if(tr[z][0]==y)tr[z][0]=x;        else tr[z][1]=x;    }    fa[x]=z;fa[y]=x;fa[tr[x][r]]=y;    tr[y][l]=tr[x][r];tr[x][r]=y;    pushup(y);pushup(x);}int get(int u,int v){    int l=1,r=m;    while(l<=r)    {        int mid=(l+r)>>1;        if(e[mid].u<u||(e[mid].u==u&&e[mid].v<v))l=mid+1;        else if(e[mid].u==u&&e[mid].v==v)return mid;        else r=mid-1;    }}void pushdown(int x){    if(!isroot(x))        pushdown(fa[x]);    int l=tr[x][0],r=tr[x][1];    if(rev[x])    {        rev[x]^=1;rev[l]^=1;rev[r]^=1;        swap(tr[x][0],tr[x][1]);    }}void splay(int x){    pushdown(x);    int y,z;    while(!isroot(x))    {        y=fa[x];z=fa[x];        if(!isroot(y))        {            if((tr[y][0]==x)^(tr[z][0]==y)) rotate(x);            else rotate(y);        }        rotate(x);    }} void access(int x){    int t=0;    while(x)    {        splay(x);tr[x][1]=t;        pushup(x);        t=x;x=fa[x];    }}void makeroot(int x){    access(x);splay(x);rev[x]^=1;}void link(int x,int y){    makeroot(x);fa[x]=y;}void cut(int x,int y){    makeroot(x);access(y);splay(y);tr[y][0]=fa[x]=0;}int query(int x,int y){    makeroot(x);access(y);splay(y);return mx[y];}int main(){    n=getint();m=getint();Q=getint();    for(int i=1;i<=n;i++)f[i]=i;    for(int i=1;i<=m;i++)    {        e[i].u=getint(),e[i].v=getint(),e[i].w=getint();        if(e[i].u>e[i].v)swap(e[i].u,e[i].v);    }    sort(e+1,e+m+1,cmp);    for(int i=1;i<=m;i++)    {        e[i].id=i;        val[n+i]=e[i].w;        mx[n+i]=n+i;    }    sort(e+1,e+m+1);    for(int i=1;i<=Q;i++)    {        q[i].f=getint();        q[i].x=getint(),q[i].y=getint();        if(q[i].f==2)        {            if(q[i].x>q[i].y)swap(q[i].x,q[i].y);            int t=get(q[i].x,q[i].y);            e[t].d=1;q[i].id=e[t].id;        }    }    sort(e+1,e+m+1,cmp2);    int tot=0;    for(int i=1;i<=m;i++)        if(!e[i].d)        {            int u=e[i].u,v=e[i].v,x=getf(u),y=getf(v);            if(x!=y)            {                f[x]=y;                link(u,i+n);link(v,i+n);                tot++;                if(tot==n-1)break;            }        }    for(int i=Q;i;i--)    {        if(q[i].f==1)            q[i].ans=val[query(q[i].x,q[i].y)];        else        {            int u=q[i].x,v=q[i].y,k=q[i].id;                int t=query(u,v);                if(e[k].w<val[t])                {                    cut(e[t-n].u,t);cut(e[t-n].v,t);                    link(u,k+n);link(v,k+n);             }        }    }    for(int i=1;i<=Q;i++)        if(q[i].f==1)printf("%d\n",q[i].ans);    return 0;}