HDU4553（线段树区间合并）

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题解:设两个区间表示屌丝剩下的区间，女神剩下的区间，然后用lazy思想更新一下，lazy = 0被更新成空闲的，lazy = 1表示这段区间被更新成屌丝的，lazy = 2表示这段区间被更新成女神的，lazy = -1表示这段区间不做任何操作。

注意一下更新屌丝的时候如果下面的是左右子区间lazy = 0时要先把左右子区间更新一下即可，这样才能确保左右子区间女神没有用

#include<iostream>#include<cstring>#include<algorithm>#include<cstdio>using namespace std;#define mid (L+R)/2#define ls rt<<1#define rs rt<<1|1#define lson ls,L,mid#define rson rs,mid+1,Rconst int mx = 1e5+5;struct node{    int lazy;    int dl,dr,dm;    int nl,nr,nm;}T[mx<<2];void built(int rt,int L,int R){    T[rt].lazy = -1;    T[rt].dl = T[rt].dr = T[rt].dm = R-L+1;    T[rt].nl = T[rt].nm = T[rt].nr = R-L+1;    if(L==R)        return;    built(lson);    built(rson);}void push_up(int rt,int L,int R){    if(mid-L+1==T[ls].dl)        T[rt].dl = T[ls].dl+T[rs].dl;    else        T[rt].dl = T[ls].dl;    if(R-mid==T[rs].dr)        T[rt].dr = T[ls].dr+T[rs].dr;    else        T[rt].dr = T[rs].dr;    T[rt].dm = max(T[ls].dr+T[rs].dl,max(T[ls].dm,T[rs].dm));    if(mid-L+1==T[ls].nl)        T[rt].nl = T[ls].nl+T[rs].nl;    else        T[rt].nl = T[ls].nl;    if(R-mid==T[rs].nr)        T[rt].nr = T[ls].nr+T[rs].nr;    else        T[rt].nr = T[rs].nr;    T[rt].nm = max(T[ls].nr+T[rs].nl,max(T[ls].nm,T[rs].nm));}void push_down(int rt,int L,int R){    if(L==R)        return;    if(T[rt].lazy!=-1){        if(T[rt].lazy==0){            T[ls].dl = T[ls].dm = T[ls].dr = T[ls].nl = T[ls].nm = T[ls].nr = mid-L+1;            T[rs].dl = T[rs].dm = T[rs].dr = T[rs].nl = T[rs].nm = T[rs].nr = R-mid;            T[ls].lazy = T[rs].lazy = 0;            T[rt].lazy = -1;        }        else if(T[rt].lazy==1){            if(T[ls].lazy==0)                push_down(ls,L,mid);            if(T[rs].lazy==0)                push_down(rs,mid+1,R);            T[ls].dl = T[ls].dm = T[ls].dr = 0;            T[rs].dl = T[rs].dm = T[rs].dr = 0;            T[ls].lazy = T[rs].lazy = 1;            T[rt].lazy = -1;        }        else if(T[rt].lazy==2){            T[ls].dl = T[ls].dm = T[ls].dr = 0;            T[rs].dl = T[rs].dm = T[rs].dr = 0;            T[ls].nl = T[ls].nm = T[ls].nr = 0;            T[rs].nl = T[rs].nm = T[rs].nr = 0;            T[ls].lazy = T[rs].lazy = 2;            T[rt].lazy = -1;        }    }}int query_ns(int rt,int L,int R,int x){    push_down(rt,L,R);    if(L==R)        return L;    if(T[ls].nm>=x)        return query_ns(lson,x);    else if(T[ls].nr+T[rs].nl>=x)        return mid-T[ls].nr+1;    else        return query_ns(rson,x);}int query_ds(int rt,int L,int R,int x){    push_down(rt,L,R);    if(L==R)        return L;    if(T[ls].dm>=x)        return query_ds(lson,x);    else if(T[ls].dr+T[rs].dl>=x)        return mid-T[ls].dr+1;    else        return query_ds(rson,x);}void update(int rt,int L,int R,int l,int r,int v){    push_down(rt,L,R);    if(l <= L&&R <= r){        if(v==0){            T[rt].dl = T[rt].dm = T[rt].dr = T[rt].nl = T[rt].nm = T[rt].nr = R-L+1;            T[rt].lazy = 0;        }        else if(v==1){            T[rt].dl = T[rt].dm = T[rt].dr = 0;            T[rt].lazy = 1;        }        else{            T[rt].dl = T[rt].dm = T[rt].dr = T[rt].nl = T[rt].nm = T[rt].nr = 0;            T[rt].lazy = 2;        }        return;    }    if(l>mid) update(rson,l,r,v);    else if(r<=mid) update(lson,l,r,v);    else{        update(lson,l,mid,v);        update(rson,mid+1,r,v);    }    push_up(rt,L,R);}int main(){    int n,q,t,casei = 1;    scanf("%d",&t);    while(t--){        scanf("%d%d",&n,&q);        update(1,1,n,1,n,0);        int ans;        printf("Case %d:\n",casei++);        while(q--){            char s[20];            int x,l,r;            scanf("%s",s);            if(s[0]=='D'){                scanf("%d",&x);                if(T[1].dm<x){                    printf("fly with yourself\n");                    continue;                }                ans = query_ds(1,1,n,x);                printf("%d,let's fly\n",ans);                update(1,1,n,ans,ans+x-1,1);            }            else if(s[0]=='N'){                scanf("%d",&x);                if(T[1].dm<x){                    if(T[1].nm<x)                        printf("wait for me\n");                    else{                        ans = query_ns(1,1,n,x);                        update(1,1,n,ans,ans+x-1,2);                        printf("%d,don't put my gezi\n",ans);                    }                }                else{                    ans = query_ds(1,1,n,x);                    update(1,1,n,ans,ans+x-1,2);                     printf("%d,don't put my gezi\n",ans);                }            }            else{                scanf("%d%d",&l,&r);                update(1,1,n,l,r,0);                printf("I am the hope of chinese chengxuyuan!!\n");            }        }    }    return 0;}

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