#include "sequence.h"
#include<bits/stdc++.h>
using namespace std;
const int N=5e5+5, INF=1e9;
int n;
struct node{
int mn, mx;
node(int mn=0, int mx=0) : mn(mn), mx(mx) {}
};
node pull(node L, node R) {
int MN, MX;
MN=min(L.mn, R.mn);
MX=max(L.mx, R.mx);
return node(MN, MX);
}
struct ST{
node tr[4*N];
int lazy[4*N];
node build(int pos=0, int l=0, int r=n) {
lazy[pos]=0;
if(l==r) return node(l, r);
int mid=l+r>>1;
return tr[pos]=pull(build(2*pos+1, l, mid), build(2*pos+2, mid+1, r));
}
void change(int pos, int add) {
tr[pos].mn+=add;
tr[pos].mx+=add;
lazy[pos]+=add;
}
void push(int pos) {
change(2*pos+1, lazy[pos]);
change(2*pos+2, lazy[pos]);
lazy[pos]=0;
}
void update(int ll, int rr, int add, int pos=0, int l=0, int r=n) {
if(ll>rr) return;
if(ll==l && rr==r) {change(pos, add); return;}
push(pos); int mid=l+r>>1;
update(ll, min(rr, mid), add, 2*pos+1, l, mid);
update(max(mid+1, ll), rr, add, 2*pos+2, mid+1, r);
tr[pos]=pull(tr[2*pos+1], tr[2*pos+2]);
}
node get(int ll, int rr, int pos=0, int l=0, int r=n) {
if(ll>rr) return node(INF, -INF);
if(ll==l && rr==r) return tr[pos];
push(pos);int mid=l+r>>1;
return pull(get(ll, min(rr, mid), 2*pos+1, l, mid), get(max(mid+1, ll), rr, 2*pos+2, mid+1, r));
}
};
int sequence(int N, vector<int> a) {
n=N;
vector<vector<int>> pos(n+1);
ST neg, pos;
neg.build();
pos.build();
for(int i=0; i<n; i++) pos[a[i]].push_back(i+1);
int ans=1;
for(int val=1; val<=n; val++) {
int SZ=pos[val].size();
for(int p : pos[val]) neg.update(p, n-1, -2);
for(int p : pos[val-1]) pos.update(p, n-1, -2);
for(int i=0; i<SZ; i++) {
while(i+ans<SZ) {
int L=pos[val][i], R=pos[val][i+ans];
int mini=neg.get(R, n).mn-neg.get(0, L-1).mx;
int maxi=pos.get(R, n).mx-pos.get(0, L-1).mn;
if(mini<=0 && maxi>=0) ans++;
}
}
}
return ans;
}
Compilation message
sequence.cpp: In member function 'node ST::build(int, int, int)':
sequence.cpp:23:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
23 | int mid=l+r>>1;
| ~^~
sequence.cpp: In member function 'void ST::update(int, int, int, int, int, int)':
sequence.cpp:39:29: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
39 | push(pos); int mid=l+r>>1;
| ~^~
sequence.cpp: In member function 'node ST::get(int, int, int, int, int)':
sequence.cpp:47:28: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
47 | push(pos);int mid=l+r>>1;
| ~^~
sequence.cpp: In function 'int sequence(int, std::vector<int>)':
sequence.cpp:55:13: error: conflicting declaration 'ST pos'
55 | ST neg, pos;
| ^~~
sequence.cpp:54:25: note: previous declaration as 'std::vector<std::vector<int> > pos'
54 | vector<vector<int>> pos(n+1);
| ^~~
sequence.cpp:57:9: error: 'class std::vector<std::vector<int> >' has no member named 'build'
57 | pos.build();
| ^~~~~
sequence.cpp:63:37: error: 'class std::vector<std::vector<int> >' has no member named 'update'
63 | for(int p : pos[val-1]) pos.update(p, n-1, -2);
| ^~~~~~
sequence.cpp:70:30: error: 'class std::vector<std::vector<int> >' has no member named 'get'
70 | int maxi=pos.get(R, n).mx-pos.get(0, L-1).mn;
| ^~~
sequence.cpp:70:47: error: 'class std::vector<std::vector<int> >' has no member named 'get'
70 | int maxi=pos.get(R, n).mx-pos.get(0, L-1).mn;
| ^~~
