[BZOJ 4850][Jsoi2016]灯塔

传送门

 #include <bits/stdc++.h>
 using namespace std;
 #define rep(i,a,b) for(int i=a;i<=b;++i)
 ;
 inline int gi() {
     ; char o; bool f=true; for(;!isdigit(o=getchar());)if(o=='-')f=false;
     )+(x<<)+(o&); ;
 }
 ][];
 int qry(int l,int r){
     ; <<L+)<=r) ++L;
     <<L)+][L]);
 }
 int n;
 inline void solve(int *a) {
     rep(i,,n) pre[i][]=h[i];
     rep(k,,) rep(i,,n)
         pre[i][k]=max(pre[i][k-],pre[i+(<<k-)][k-]);
     rep(i,,n) {
         ,L=i+,R,ret=;
         while(L<=n) {
             R=i+(op+)*(op+); R=min(R,n);
             ++ op;
             ret=max(ret,qry(L,R)+op); L=R+;
         }
         a[i]=max(,ret-h[i]);
     }
 }
 int main() {
     n=gi();rep(i,,n) h[i]=gi();
     solve(f);
     reverse(h+,h++n);
     solve(g);
     rep(i,,n) printf(]));
     ;
 }

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