[BZOJ 4923][Lydsy1706月赛]K小值查询

传送门

势能分析平衡树，splay或treap都可以

放个指针版的就跑

 #include <bits/stdc++.h>
 using namespace std;
 #define rep(i,a,b) for(int i=a;i<=b;++i)
 ;
 template <class T> inline bool check_Max(T &x, const T&y) { return x<y?x=y,false:true;}
 template <class T> inline bool check_Min(T &x, const T&y) { return x>y?x=y,false:true;}
 inline int gi() {
     ; char o; bool f=true; for(;!isdigit(o=getchar());) if(o=='-') f=false;
     )+(x<<)+(o&); ;
 }
 struct node {int v,ky,sz,lz; node *ls,*rs;}*rt,*nul,pool[maxn],*pis=pool;
 inline ; rt=nul;}
 node *newnode(; k->sz=; return k;}
 inline void add(node *&x,int vl) { x->v+=vl; x->lz+=vl; return ;}
 inline void pd(node *&x) {
     ;
 }
 inline ; }
 inline void mrg(node *&c,node *x,node *y) {
     if(x==nul||y==nul) {c=x==nul?y:x; return;}
     pd(x); pd(y);
     if(x->ky < y->ky) c=x,mrg(c->rs,x->rs,y);
     else c=y,mrg(c->ls,x,y->ls); up(c);
 }
 inline void spl(node *c,node *&x,node *&y,int rk) {
     if(c==nul) { x=y=nul; return;}
     pd(c);
     if(c->v <= rk) x=c,spl(c->rs,x->rs,y,rk);
     else y=c,spl(c->ls,x,y->ls,rk); up(c);
 }
 inline void insert(int vl) {
     node *x,*y; spl(rt,x,y,vl);
     mrg(x,x,newnode(vl)); mrg(rt,x,y);
 }
 int find(node *&x,int rk) {
     ==rk) return x->v;
     pd(x);
     if(rk<=x->ls->sz) return find(x->ls,rk);
     );
 }
 inline void rec(node *&now,node *&x,int vl) {
     if(x==nul) return; pd(x); rec(now,x->ls,vl); rec(now,x->rs,vl);
     x->ls=x->rs=nul; x->sz=; x->v-=vl;
     node *x1,*y1; spl(now,x1,y1,x->v); mrg(x1,x1,x); mrg(now,x1,y1);
 }
 inline void cg(int k) {
     node *x,*y,*z; spl(rt,x,y,k); spl(y,y,z,k<<);
     add(z,-k); rec(x,y,k); mrg(rt,x,z);
 }
 int n,m;
 int main() {
 #ifndef ONLINE_JUDGE
     freopen("3.in","r",stdin);
     freopen("a.out","w",stdout);
 #endif
     n=gi();m=gi();
     init();
     rep(i,,n) insert(gi());
     rep(i,,m) {
         int opt=gi(),K=gi();
         ) printf("%d\n",find(rt,K));
         else cg(K);
     }
     ;
 }

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