POJ 2761 Feed the dogs

Feed the dogs

Time Limit: 6000MS		Memory Limit: 65536K
Total Submissions: 11808		Accepted: 3409

Description

Wind loves pretty dogs very much, and she has n pet dogs. So Jiajia has to feed the dogs every day for Wind. Jiajia loves Wind, but not the dogs, so Jiajia use a special way to feed the dogs. At lunchtime, the dogs will stand on one line, numbered from 1 to n, the leftmost one is 1, the second one is 2, and so on. In each feeding, Jiajia choose an inteval[i,j], select the k-th pretty dog to feed. Of course Jiajia has his own way of deciding the pretty value of each dog. It should be noted that Jiajia do not want to feed any position too much, because it may cause some death of dogs. If so, Wind will be angry and the aftereffect will be serious. Hence any feeding inteval will not contain another completely, though the intervals may intersect with each other.

Your task is to help Jiajia calculate which dog ate the food after each feeding.

Input

The first line contains n and m, indicates the number of dogs and the number of feedings.

The second line contains n integers, describe the pretty value of each dog from left to right. You should notice that the dog with lower pretty value is prettier.

Each of following m lines contain three integer i,j,k, it means that Jiajia feed the k-th pretty dog in this feeding.

You can assume that n<100001 and m<50001.

Output

Output file has m lines. The i-th line should contain the pretty value of the dog who got the food in the i-th feeding.

Sample Input

7 2

1 5 2 6 3 7 4

1 5 3

2 7 1

Sample Output

3

2

Source

POJ Monthly--2006.02.26,zgl & twb

//早上起来说吧昨天写的的SBT练习一下、然后、一早上就渡过去了、

//中间出了许多小问题、、、悲惨，万恶的复制、粘贴呀

 

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <cmath>
#include <queue>
#define N 100013
using namespace std;
struct node
{
    int l,r,s,key;
    void init()
    {
        l=r=key=0;
        s=1;
    }
};
node sbt[N];
int nu;
void right_rotate(int &t)
{
    int k=sbt[t].l;
    sbt[t].l=sbt[k].r;
    sbt[k].r=t;
    sbt[k].s=sbt[t].s;
    sbt[t].s=sbt[sbt[t].l].s+sbt[sbt[t].r].s+1;
    t=k;
}
void left_rotate(int &t)
{
    int k=sbt[t].r;
    sbt[t].r=sbt[k].l;
    sbt[k].l=t;     //开始这里错了
    sbt[k].s=sbt[t].s;
    sbt[t].s=sbt[sbt[t].l].s+sbt[sbt[t].r].s+1;
    t=k;
}
void Maintain(int &t,bool flag)
{
    if(flag==false)
    {
        if(sbt[sbt[sbt[t].l].l].s>sbt[sbt[t].r].s)
             right_rotate(t);
        else if(sbt[sbt[sbt[t].l].r].s>sbt[sbt[t].r].s)
              left_rotate(sbt[t].l),right_rotate(t);
              else return ;
    }
    else
    {
        if(sbt[sbt[sbt[t].r].r].s>sbt[sbt[t].l].s)
              left_rotate(t);
        else if(sbt[sbt[sbt[t].r].l].s>sbt[sbt[t].l].s)
              right_rotate(sbt[t].r),left_rotate(t);//该死的复制粘贴、这里又出了问题
              else return ;
    }
    Maintain(sbt[t].l,false);
    Maintain(sbt[t].r,true);
    Maintain(t,false);
    Maintain(t,true);
}
void insert(int &t,int &v)
{
    if(t==0)
    {
        t=++nu;
        sbt[t].init();
        sbt[t].key=v;
        return ;
    }
    sbt[t].s++;
    if(v<=sbt[t].key)
     insert(sbt[t].l,v);
    else
     insert(sbt[t].r,v);
    Maintain(t,v>sbt[t].key);
    return ;
}
int del(int &t,int v)
{
    if(t==0) return 0;//开始没写这个、出现负数了都、、
    sbt[t].s--;      
    if(v==sbt[t].key||(v>sbt[t].key&&!sbt[t].r)||(v<sbt[t].key&&!sbt[t].l))
    {

        if(!sbt[t].l||!sbt[t].r)//把问题都搞定后、这里少了个 '!'，然后华丽丽的WA了
        {     int k=sbt[t].key;
              t=sbt[t].r+sbt[t].l;
              return k;
        }
        else
        {
            return sbt[t].key=del(sbt[t].l,v+1);
        }
    }
    if(v>sbt[t].key)
     return del(sbt[t].r,v);
    return del(sbt[t].l,v);
}
int getkth(int &t,int k)
{
    if(k==sbt[sbt[t].l].s+1)
     return sbt[t].key;
    if(k<sbt[sbt[t].l].s+1)
      return getkth(sbt[t].l,k);
    return getkth(sbt[t].r,k-sbt[sbt[t].l].s-1);
}
struct inteval
{
    int i,j,k;
    int index,record;
};
inteval sor_t[50003];
bool cmp1(const inteval&a,const inteval&b)
{
    return a.i<b.i;
}
bool cmp2(const inteval&a,const inteval&b)
{
    return  a.index<b.index;
}
int re[N];
int main()
{
    nu=0;
    int root=0;
    int n,m,i,j;
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)
     scanf("%d",&re[i]);
    for(i=0;i<m;i++)
     {
         scanf("%d%d%d",&sor_t[i].i,&sor_t[i].j,&sor_t[i].k);
         sor_t[i].index=i;
     }

    sort(sor_t,sor_t+m,cmp1);

    for(i=sor_t[0].i;i<=sor_t[0].j;i++)
        insert(root,re[i]);
     sor_t[0].record=getkth(root,sor_t[0].k);
     for(i=1;i<m;i++)
     {
        if(sor_t[i].i>sor_t[i-1].j)
        {
            for(j=sor_t[i-1].i;j<=sor_t[i-1].j;j++)
               del(root,re[j]);
            for(j=sor_t[i].i;j<=sor_t[i].j;j++)
               insert(root,re[j]);
            sor_t[i].record=getkth(root,sor_t[i].k);
        }
        else
        {
            for(j=sor_t[i-1].i;j<sor_t[i].i;j++)//万恶的复制粘贴呀
                 del(root,re[j]);
            for(j=sor_t[i-1].j+1;j<=sor_t[i].j;j++)
                 insert(root,re[j]);
            sor_t[i].record=getkth(root,sor_t[i].k);
        }
     }
     sort(sor_t,sor_t+m,cmp2);
     for(i=0;i<m;i++)
       printf("%d\n",sor_t[i].record);
    return 0;
}