题意:http://acm.hdu.edu.cn/showproblem.php?pid=1540

#define IOS ios_base::sync_with_stdio(0); cin.tie(0);
#include <cstdio>//sprintf islower isupper
#include <cstdlib>//malloc exit strcat itoa system("cls")
#include <iostream>//pair
#include <fstream>//freopen("C:\\Users\\13606\\Desktop\\草稿.txt","r",stdin);
#include <bitset>
//#include <map>
//#include<unordered_map>
#include <vector>
#include <stack>
#include <set>
#include <string.h>//strstr substr
#include <string>
#include <time.h>//srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;
#include <cmath>
#include <deque>
#include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less
#include <vector>//emplace_back
//#include <math.h>
//#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor
#include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)
using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation
//******************
int abss(int a);
int lowbit(int n);
int Del_bit_1(int n);
int maxx(int a,int b);
int minn(int a,int b);
double fabss(double a);
void swapp(int &a,int &b);
clock_t __STRAT,__END;
double __TOTALTIME;
void _MS(){__STRAT=clock();}
void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}
//***********************
#define rint register int
#define fo(a,b,c) for(rint a=b;a<=c;++a)
#define fr(a,b,c) for(rint a=b;a>=c;--a)
#define mem(a,b) memset(a,b,sizeof(a))
#define pr printf
#define sc scanf
#define ls rt<<1
#define rs rt<<1|1
typedef long long ll;
const double E=2.718281828;
const double PI=acos(-1.0);
//const ll INF=(1LL<<60);
const int inf=(<<);
const double ESP=1e-;
const int mod=(int)1e9+;
const int N=(int)1e6+; struct node
{
int l,r;
int lmax,rmax,len;
}tr[N<<]; void up(int rt)
{
tr[rt].rmax=tr[rs].rmax;
if(tr[rs].rmax==tr[rs].len)tr[rt].rmax=tr[rs].len+tr[ls].rmax;
tr[rt].lmax=tr[ls].lmax;
if(tr[ls].lmax==tr[ls].len)tr[rt].lmax=tr[ls].len+tr[rs].lmax;
}
void Build(int l,int r,int rt)
{
tr[rt].l=l;
tr[rt].r=r;
tr[rt].len=r-l+;
tr[rt].lmax=tr[rt].rmax=r-l+;
if(l==r)return;
int mid=l+r>>;
Build(l,mid,ls);
Build(mid+,r,rs);
// up(rt);
}
void Delete(int pos,int l,int r,int rt)
{
if(l==r)
{
tr[rt].lmax=tr[rt].rmax=;
return;
}
int mid=l+r>>;
if(pos<=mid)Delete(pos,l,mid,ls);
else Delete(pos,mid+,r,rs);
up(rt);
}
void Rebuild(int pos,int l,int r,int rt)
{
if(l==r)
{
tr[rt].lmax=tr[rt].rmax=;
return;
}
int mid=l+r>>;
if(pos<=mid)Rebuild(pos,l,mid,ls);
else Rebuild(pos,mid+,r,rs);
up(rt);
}
int QnumL(int pos,int l,int r,int rt)
{
if(pos>=r)return tr[rt].rmax;
int mid=l+r>>;
if(pos>mid)
{
if(tr[rs].lmax<pos-tr[rs].l+)
{
return max(QnumL(pos,mid+,r,rs),tr[rs].rmax-(tr[rs].r-pos+)+);
}
else return pos-tr[rs].l++tr[ls].rmax;
}
else return QnumL(pos,l,mid,ls);
}
int QnumR(int pos,int l,int r,int rt)
{
if(pos<=l)return tr[rt].lmax;
int mid=l+r>>;
if(pos<=mid)
{
if(tr[ls].rmax<tr[ls].r-pos+)
{
return max(QnumR(pos,l,mid,ls),tr[ls].lmax-(pos-tr[ls].l+)+);
}
else return tr[ls].r-pos++tr[rs].lmax;
}
else return QnumR(pos,mid+,r,rs);
} int op[N];
bool D[N];
int main()
{
int n,m;
while(~sc("%d%d",&n,&m))
{
int cnt=;
Build(,n,);
for(int i=;i<=n;++i)
D[i]=;
for(int i=;i<=m;++i)
{
char j[];
int pos=;
sc("%s",j);
if(j[]!='R')sc("%d",&pos); if(j[]=='D')
Delete(pos,,n,),op[++cnt]=pos,D[op[cnt]]=;
else if(j[]=='Q')
{
if(D[pos]==)
{
pr("0\n");
continue;
}
int ansl=QnumL(pos,,n,);
int ansr=QnumR(pos,,n,);
pr("%d\n",ansl+ansr+(ansl||ansr?-:));
}
else Rebuild(op[cnt],,n,),D[op[cnt]]=,cnt--;
}
}
return ;
} /**************************************************************************************/ int maxx(int a,int b)
{
return a>b?a:b;
} void swapp(int &a,int &b)
{
a^=b^=a^=b;
} int lowbit(int n)
{
return n&(-n);
} int Del_bit_1(int n)
{
return n&(n-);
} int abss(int a)
{
return a>?a:-a;
} double fabss(double a)
{
return a>?a:-a;
} int minn(int a,int b)
{
return a<b?a:b;
}
05-11 20:28