[BZOJ4399]魔法少女LJJ(线段树合并)

请仔细阅读数据范围，c<=7.
线段树合并裸题，对于乘积大小比较，使用log即可。

#include<cmath>
#include<cstdio>
#include<cstring>
#include<algorithm>
#define lson ls[x],L,mid
#define rson rs[x],mid+1,R
#define rep(i,l,r) for (int i=(l); i<=(r); i++)
using namespace std;

const int N=400010,K=N*16,M=1000000000;
int Q,op,n,x,y,k,nd,rt[N],fa[N],sz[K],ls[K],rs[K];
double sm[K];

int get(int x){ return (fa[x]==x) ? x : fa[x]=get(fa[x]); }

void ins(int &x,int L,int R,int pos,int k){
    if (!x) x=++nd;
    if (L==R){ sz[x]+=k; sm[x]+=k*log(L); return; }
    int mid=(L+R)>>1;
    if (pos<=mid) ins(lson,pos,k); else ins(rson,pos,k);
    sz[x]=sz[ls[x]]+sz[rs[x]]; sm[x]=sm[ls[x]]+sm[rs[x]];
}

int mdf0(int &x,int L,int R,int k){
    if (!x) return 0;
    if (L==R){ if (k>L) { x=0; return 1; } else return 0; }
    int mid=(L+R)>>1,res=0;
    if (k>mid) res+=sz[ls[x]],ls[x]=0,res+=mdf0(rson,k);
        else res=mdf0(lson,k);
    sz[x]=sz[ls[x]]+sz[rs[x]]; sm[x]=sm[ls[x]]+sm[rs[x]];
    return res;
}

int mdf1(int &x,int L,int R,int k){
    if (!x) return 0;
    if (L==R){ if (k<L) { x=0; return 1; } else return 0; }
    int mid=(L+R)>>1,res=0;
    if (k<=mid) res+=sz[rs[x]],rs[x]=0,res+=mdf1(lson,k);
        else res=mdf1(rson,k);
    sz[x]=sz[ls[x]]+sz[rs[x]]; sm[x]=sm[ls[x]]+sm[rs[x]];
    return res;
}

int merge(int x,int y,int L,int R){
    if (!x || !y) return x+y;
    sz[x]+=sz[y]; sm[x]+=sm[y];
    if (L<R){
        int mid=(L+R)>>1;
        ls[x]=merge(ls[x],ls[y],L,mid);
        rs[x]=merge(rs[x],rs[y],mid+1,R);
    }
    return x;
}

int find(int x,int L,int R,int k){
    if (L==R) return L;
    int mid=(L+R)>>1;
    if (k<=sz[ls[x]]) return find(lson,k);
        else return find(rson,k-sz[ls[x]]);
}

int main(){
    freopen("bzoj4399.in","r",stdin);
    freopen("bzoj4399.out","w",stdout);
    for (scanf("%d",&Q); Q--; ){
        scanf("%d",&op);
        if (op==1) scanf("%d",&x),n++,fa[n]=n,ins(rt[n],1,M,x,1);
        if (op==2){
            scanf("%d%d",&x,&y); int p=get(x),q=get(y);
            if (p==q) continue;
            rt[p]=merge(rt[p],rt[q],1,M); fa[q]=p;
        }
        if (op==3) scanf("%d%d",&x,&k),ins(rt[get(x)],1,M,k,mdf0(rt[get(x)],1,M,k));
        if (op==4) scanf("%d%d",&x,&k),ins(rt[get(x)],1,M,k,mdf1(rt[get(x)],1,M,k));
        if (op==5) scanf("%d%d",&x,&k),printf("%d
",find(rt[get(x)],1,M,k));
        if (op==6) scanf("%d%d",&x,&y),printf("%d
",(int)(sm[rt[get(x)]]>sm[rt[get(y)]]));
        if (op==7) scanf("%d",&x),printf("%d
",sz[rt[get(x)]]);
    }
    return 0;
}