一道碼農題......

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具體算法用splay或fhq_treep都行，網上也有，放個指針版的就跑！

  1 #include <bits/stdc++.h>
  2 using namespace std;
  3 #define rep(i,a,b) for(int i=a;i<=b;++i)
  4 const int maxn=500010,inf=0x3f3f3f3f;
  5 inline int gi() {
  6     int x=0;char o;bool f=true;for(;!isdigit(o=getchar());)if(o==‘
 
-‘)f=false;
  7     for(;isdigit(o);o=getchar())x=(x<<1)+(x<<3)+(o&15);return f?x:~x+1;
  8 }
  9 //namespace fhq {
 10     struct node{int vl,sz,ky,lx,rx,sm,mrk,cvr,pri;node *ls,*rs;};
 11     int bc_top;
 12     node *rt,*nul,pool[maxn],*pis=pool,*bc[maxn];
 13     inline void init() {
 
 14         nul=pis; nul->ls=nul->rs=nul;
 15         bc_top=0; rt=nul;
 16         nul->vl=nul->sz=nul->lx=nul->rx=nul->sm=nul->mrk=0;
 17         nul->pri=-inf;
 18         nul->cvr=inf;
 19     }
 20     inline node *newnode(int x) {
 21         node *k=bc_top?bc[bc_top--]:++pis; 
 
 22         k->ls=k->rs=nul; k->vl=k->lx=k->rx=k->sm=k->pri=x;
 23         k->mrk=0; k->sz=1;
 24         k->cvr=inf; k->ky=rand(); return k;
 25     }
 26     inline void zuan(node *&x) {swap(x->ls,x->rs); swap(x->lx,x->rx); x->mrk^=1;}
 27     inline void covered(node *&x,int v){
 28         x->vl=v; x->sm=x->sz*v; x->lx=x->rx=max(v,x->sm);
 29         x->cvr=v; x->pri=max(v,x->sm);
 30     }
 31     inline void pd(node *&x) {
 32         if(x==nul) return;
 33         if(x->mrk) {
 34             if(x->ls!=nul) zuan(x->ls); if(x->rs!=nul) zuan(x->rs);
 35         }
 36         if(x->cvr!=inf) {
 37             if(x->ls!=nul) covered(x->ls,x->cvr); if(x->rs!=nul) covered(x->rs,x->cvr);
 38         }
 39         x->mrk=0;x->cvr=inf;
 40     }
 41     inline void updata(node *&x) {
 42         if(x==nul) return ;
 43         node *L=x->ls,*R=x->rs;
 44         pd(x);
 45         x->lx=max(L->lx,L->sm+x->vl+max(0,R->lx));
 46         x->rx=max(R->rx,R->sm+x->vl+max(0,L->rx));
 47         x->pri=max(max(L->pri,R->pri),x->vl+max(0,L->rx)+max(0,R->lx));
 48         x->sz=L->sz+R->sz+1; 
 49         x->sm=L->sm+R->sm+x->vl;
 50     }
 51     inline void mrg(node *&c,node *x,node *y) {
 52         if(x==nul||y==nul) {c = x==nul?y:x;return ;}
 53         pd(x);pd(y);
 54         if(x->ky < y->ky) c=x,mrg(c->rs,x->rs,y);
 55         else c=y,mrg(c->ls,x,y->ls);
 56         updata(c);
 57     }
 58     inline void spl(node *c,node *&x,node *&y,int sz) {
 59         if(c==nul) {x=y=nul;return ;}
 60         pd(c);
 61         if(c->ls->sz >= sz) y=c,spl(c->ls,x,y->ls,sz);
 62         else x=c,spl(c->rs,x->rs,y,sz-c->ls->sz-1);
 63         updata(c);
 64     }
 65     inline void insert(int x) {mrg(rt,rt,newnode(x));}
 66     inline void fuze(int l,int r) {
 67         node *x,*y,*z;spl(rt,x,y,r); spl(x,x,z,l-1);
 68         zuan(z); mrg(x,x,z); mrg(rt,x,y); return;
 69     }
 70     inline void cover(int l,int r,int v) {
 71         node *x,*y,*z;spl(rt,x,y,r); spl(x,x,z,l-1);
 72         covered(z,v); mrg(x,x,z); mrg(rt,x,y); return;
 73     }
 74     inline void rec(node *x) {if(x==nul) return; bc[++bc_top]=x; rec(x->ls); rec(x->rs);}
 75     inline void delet(int l,int r) {node *x,*y,*z; spl(rt,x,y,r); spl(x,x,z,l-1); rec(z); mrg(rt,x,y);}
 76     inline void add() {
 77         int pos=gi(),tot=gi(); node *x,*y; spl(rt,x,y,pos);
 78         rep(i,1,tot) mrg(x,x,newnode(gi())); mrg(rt,x,y);
 79     }
 80     inline void outs(int l,int r){
 81         node *x,*y,*z; 
 82         spl(rt,x,y,r); spl(x,x,z,l-1);
 83         printf("%d\n",z->sm); 
 84         mrg(x,x,z); mrg(rt,x,y);
 85     }
 86 //}
 87 int n,m; char opt[50];
 88 int main() {
 89 #ifndef ONLINE_JUDGE
 90     freopen("4.in","r",stdin);
 91     freopen("a.out","w",stdout);
 92 #endif
 93     init(); 
 94     n=gi(); m=gi(); rep(i,1,n) insert(gi());
 95     rep(i,1,m) {
 96         scanf("%s",opt);
 97         if(*opt==‘G‘) {int l=gi(),r=gi();outs(l,r+l-1);}
 98         else if(*opt==‘D‘) {int l=gi(),r=gi();delet(l,r+l-1);}
 99         else if(*opt==‘R‘) {int l=gi(),r=gi();fuze(l,r+l-1);}
100         else if(*opt==‘I‘) add();
101         else if(opt[2]==‘X‘) updata(rt),printf("%d\n",rt->pri);
102         else {int l=gi(),r=gi(),v=gi();cover(l,r+l-1,v);}
103     }
104     return 0;
105 }

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