http://acm.hdu.edu.cn/showproblem.php?pid=2871&&Memory Control

线段树之区间合并+二分查找，和hotel哪一题类似，，

AC代码：

#include <iostream>
#include<string.h>
#include<algorithm>
#include<vector>
#include<cstdio>
#define CLR(arr,val) memset(arr,val,sizeof(arr))
#define N 50005
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define M(a,b) (a+b)>>1
using namespace std;
typedef struct{
   int r;
   int l;
   int lsum;
   int rsum;
   int msum;
   int col;
}Tree;
Tree Node[N<<2];
typedef struct {
    int x;
    int y;
}Block;
bool cmp(const Block& a,const Block& b)
{
    return a.x<b.x;
}
int Max(int a,int b,int c){
   a=a>b?a:b;
   a=a>c?a:c;
   return a;
}
vector<Block>v;
void push_down(int rt,int s){
    if(Node[rt].col!=-1){
        Node[rt<<1].col=Node[rt<<1|1].col=Node[rt].col;
        Node[rt<<1].lsum=Node[rt<<1].rsum=Node[rt<<1].msum= Node[rt].col?s-(s>>1):0;
        Node[rt<<1|1].lsum=Node[rt<<1|1].rsum=Node[rt<<1|1].msum=Node[rt].col?(s>>1):0;
        Node[rt].col=-1;
        }
}
void push_up(int rt,int s){

  Node[rt].lsum=Node[rt<<1].lsum;
  Node[rt].rsum=Node[rt<<1|1].rsum;
  if(Node[rt<<1].lsum==(s-(s>>1))) Node[rt].lsum+=Node[rt<<1|1].lsum;
  if(Node[rt<<1|1].rsum==(s>>1)) Node[rt].rsum+=Node[rt<<1].rsum;
  Node[rt].msum=Max(Node[rt<<1].msum,Node[rt<<1|1].msum,Node[rt<<1].rsum+Node[rt<<1|1].lsum);
}
void build(int l,int r,int rt){
 if(l==r){
         Node[rt].l=Node[rt].r=l;
         Node[rt].lsum=Node[rt].rsum=Node[rt].msum=1;
         Node[rt].col=-1;
         return;
        }
        int m=M(l,r);
        build(lson);
        build(rson);
        Node[rt].l=l;
        Node[rt].r=r;
        Node[rt].lsum=Node[rt].rsum=Node[rt].msum=r-l+1;
        Node[rt].col=-1;

}
void updata(int L,int R,int cnt,int l,int r,int rt)
{
    if(L<=l&&R>=r){
        Node[rt].col=cnt;
        Node[rt].lsum=Node[rt].rsum=Node[rt].msum=cnt?r-l+1:0;
        return;
                }
        push_down(rt,r-l+1);
        int m=M(l,r);
        if(L<=m) updata(L,R,cnt,lson);
        if(R>m) updata(L,R,cnt,rson);
        push_up(rt,r-l+1);
}
int Quary(int p,int l,int r,int rt){
 if(l==r) return l;
 push_down(rt,r-l+1);
 int m=M(l,r);
 if(Node[rt<<1].msum>=p) return Quary(p,lson);
 else if((Node[rt<<1].rsum+Node[rt<<1|1].lsum)>=p) return (m-Node[rt<<1].rsum+1);
 return Quary(p,rson);
}
void in(int &a)
{
    char ch;
    while((ch=getchar())<'0'||ch>'9');
    for( a=0;ch>='0'&&ch<='9';ch=getchar()) a=a*10+ch-'0';

}
int n,m;

int main()
{
    while(~scanf("%d%d",&n,&m))
    {
        char ch[10];
        build(1,n,1);
        v.clear();
        while(m--){
           scanf("%s",ch);
           if(ch[0]=='N'){
               int a;in(a);
               if(Node[1].msum<a) printf("Reject New\n");
               else{
                     int ans=Quary(a,1,n,1);
                     printf("New at %d\n",ans);
                     updata(ans,ans+a-1,0,1,n,1);
                     Block pos;
                     pos.x=ans,pos.y=ans+a-1;
                     vector<Block>::iterator it=upper_bound(v.begin(),v.end(),pos,cmp);
                     v.insert(it,pos);
                   }
           }
           else if(ch[0]=='F'){
                int a;in(a);
                Block pos;
                pos.x=a,pos.y=a;
                vector<Block>::iterator it=upper_bound(v.begin(),v.end(),pos,cmp);
                int ans=it-v.begin()-1;
                if(ans==-1||v[ans].y<a) printf("Reject Free\n");
                else {
                    printf("Free from %d to %d\n",v[ans].x,v[ans].y);
                    updata(v[ans].x,v[ans].y,1,1,n,1);
                    v.erase(v.begin()+ans);
                    }
                }
           else if(ch[0]=='R'){
               printf("Reset Now\n");
               v.clear();
               updata(1,n,1,1,n,1);
           }
           else {
                   int a;in(a);
                   if(v.size()>=a) printf("Get at %d\n",v[a-1].x);
                   else printf("Reject Get\n");

                }
           }
           printf("\n");
        }return 0;
    }