#include "sequence_apio23.h"
#include <bits/stdc++.h>
using namespace std;
#define pf printf
#define pb push_back
#define maxn 500005
struct node{
int N,mn[maxn<<2],mx[maxn<<2],lz[maxn<<2];
void ppo(int i,int s,int e){
mx[i]+=lz[i];
mn[i]+=lz[i];
if(s!=e){
lz[2*i+1]+=lz[i];
lz[2*i+2]+=lz[i];
}
lz[i]=0;
}
void up(int i,int s,int e,int x,int y,int nv){
if(s==x&&e==y){lz[i]+=nv;return;}
int m=(s+e)>>1;
if(y<=m)up(2*i+1,s,m,x,y,nv);
else if(x>m)up(2*i+2,m+1,e,x,y,nv);
else up(2*i+1,s,m,x,m,nv),up(2*i+2,m+1,e,m+1,y,nv);
ppo(2*i+1,s,m);
ppo(2*i+2,m+1,e);
mn[i]=min(mn[2*i+1],mn[2*i+2]);
mx[i]=max(mx[2*i+1],mx[2*i+2]);
}
inline void up(int x,int y,int nv){
up(0,0,N,x,y,nv);
}
int qmx(int i,int s,int e,int x,int y){
if(s==x&&e==y)return mx[i]+lz[i];
ppo(i,s,e);
int m=(s+e)>>1;
if(y<=m)return qmx(2*i+1,s,m,x,y);
if(x>m)return qmx(2*i+2,m+1,e,x,y);
return max(qmx(2*i+1,s,m,x,m),qmx(2*i+2,m+1,e,m+1,y));
}
inline int qmx(int x,int y){
return qmx(0,0,N,x,y);
}
int qmn(int i,int s,int e,int x,int y){
if(s==x&&e==y)return mn[i]+lz[i];
ppo(i,s,e);
int m=(s+e)>>1;
if(y<=m)return qmn(2*i+1,s,m,x,y);
if(x>m)return qmn(2*i+2,m+1,e,x,y);
return min(qmn(2*i+1,s,m,x,m),qmn(2*i+2,m+1,e,m+1,y));
}
inline int qmn(int x,int y){
return qmn(0,0,N,x,y);
}
}prt,srt;
int pmn[maxn],pmx[maxn],smn[maxn],smx[maxn],tot[maxn][2];
vector<int> v[maxn];
//a range is valid if sum(>=x)-sum(<x)>=0 --> find min: == x value 1
//and sum(>x)-sum(<=x)<=0 --> find max: == x value -1
inline bool check(int i,int l,int r){
return (tot[i][0]-pmn[l]-smn[r]>=0)&&(tot[i][1]-pmx[l]-smx[r]<=0);
}
int sequence(int N,vector<int> A){
prt.N=srt.N=N+1;
for(int i=0;i<N;++i){
v[A[i]].pb(i+1);
prt.up(i+1,N+1,1);
srt.up(0,i+1,1);
}
for(int i=1;i<=N;++i){
for(int x:v[i]){
pmn[x]=prt.qmn(0,x-1);
smn[x]=srt.qmn(x+1,N+1);
}
tot[i][0]=prt.qmx(N,N);
for(int x:v[i]){
prt.up(x,N+1,-2);
srt.up(0,x,-2);
}
tot[i][1]=prt.qmx(N,N);
for(int x:v[i]){
pmx[x]=prt.qmx(0,x-1);
smx[x]=srt.qmx(x+1,N+1);
}
}
int ans=0;
for(int i=1;i<=N;++i){
if(v[i].empty())continue;
int l=0,r=0;
while(r<v[i].size()){
assert(l<=r);
if(check(i,v[i][l],v[i][r])){
ans=max(ans,r-l+1);
++r;
}
else ++l;
}
}
return ans;
}
Compilation message
sequence.cpp:1:10: fatal error: sequence_apio23.h: No such file or directory
1 | #include "sequence_apio23.h"
| ^~~~~~~~~~~~~~~~~~~
compilation terminated.
