Submission #877748

#	Time	Username	Problem	Language	Result	Execution time	Memory
877748		dimashhh	Sequence (APIO23_sequence)	C++17	100 / 100	1237 ms	70676 KiB

sequence

#include <bits/stdc++.h>
#include "sequence.h"
using namespace std;
const int N = 5e5 + 1;
typedef long long ll;

int n;
struct segtree{
    int mn[N * 4],mx[N * 4],add[N * 4];
    void build(int v = 1,int tl = 1,int tr = n){
        add[v] = mn[v] = mx[v] = 0;
        if(tl == tr) return;
        int tm = (tl + tr) >> 1;
        build(v + v,tl,tm);build(v + v + 1,tm + 1,tr);
    }
    void inc(int v,int val){
        add[v] += val;
        mn[v] += val;
        mx[v] += val;
    }
    void push(int v){
        if(add[v]){
            inc(v + v,add[v]);
            inc(v + v +1,add[v]);
            add[v] = 0;
        }
    }
    void upd(int l,int r,int val,int v = 1,int tl = 1,int tr = n){
        if(l > r || tl > r || l > tr){
            return;
        }
        if(tl >= l && tr <= r){
            inc(v,val);
        }else{
            push(v);
            int tm = (tl + tr) >> 1;
            upd(l,r,val,v+v,tl,tm);
            upd(l,r,val,v+v+1,tm+1,tr);
            mn[v] = min(mn[v + v],mn[v + v + 1]);
            mx[v] = max(mx[v + v],mx[v + v + 1]);
        }
    }
    int get_min(int l,int r,int v = 1,int tl = 1,int tr = n){
        if(l > r || tl > r || l > tr) return 1e9;
        if(tl >= l && tr <= r) return mn[v];
        push(v);
        int tm = (tl + tr) >> 1;
        mn[v] = min(mn[v + v],mn[v + v + 1]);
        mx[v] = max(mx[v + v],mx[v + v + 1]);
        return min(get_min(l,r,v+v,tl,tm),get_min(l,r,v+v+1,tm+1,tr));
    }
    int get_max(int l,int r,int v = 1,int tl = 1,int tr = n){
        if(l > r || tl > r || l > tr) return -1e9;
        if(tl >= l && tr <= r) return mx[v];
        push(v);
        int tm = (tl + tr) >> 1;
        mn[v] = min(mn[v + v],mn[v + v + 1]);
        mx[v] = max(mx[v + v],mx[v + v + 1]);
        return max(get_max(l,r,v+v,tl,tm),get_max(l,r,v+v+1,tm+1,tr));
    }
}T,T1;
vector<int> pos[N];
bool inter(int l,int r,int l1,int r1){
    return (min(r,r1) - max(l,l1) >= 0);
}
int sequence(int nn, std::vector<int> a) {
    n = nn;
    int mn = 1e9;
    for(int i = 0;i < nn;i++){
        mn = min(mn,a[i]);
        pos[a[i]].push_back(i + 1);
    }
    T.build();
    T1.build();
    for(int i = 1;i <= n;i++){
        T.upd(i,n,1);
        T1.upd(i,n,1);
    }
    int res = 1;
    for(int i = 1;i <= n;i++){
        for(int j:pos[i - 1]){
            T.upd(j,n,-2);
        }
        for(int j:pos[i]){
            T1.upd(j,n,-2);
        }
        int it = 0;
        for(int j = 0;j < (int)pos[i].size();j++){
            while(it < (int)pos[i].size()){
                ll mn_sum = T1.get_min(pos[i][it],n) - max(0,T1.get_max(1,pos[i][j] - 1));
                ll mx_sum = T.get_max(pos[i][it],n) - min(0,T.get_min(1,pos[i][j] - 1));
                int len = (it - j + 1);
                if(mn_sum * mx_sum <=0 ){
                    it++;
                }else{
                    break;  
                }
            }
            res = max(res,it - j);
        }
    }
    return res;

}

// int main() {
//   int N;
//   assert(1 == scanf("%d", &N));

//   std::vector<int> A(N);
//   for (int i = 0; i < N; ++i) {
//     assert(1 == scanf("%d", &A[i]));
//   }

//   int result = sequence(N, A);
//   printf("%d\n", result);
//   return 0;
// }

Compilation message (stderr)

sequence.cpp: In function 'int sequence(int, std::vector<int>)':
sequence.cpp:92:21: warning: unused variable 'len' [-Wunused-variable]
   92 |                 int len = (it - j + 1);
      |                     ^~~

• Subtask 1: 11 / 11
• Subtask 2: 17 / 17
• Subtask 3: 7 / 7
• Subtask 4: 12 / 12
• Subtask 5: 13 / 13
• Subtask 6: 22 / 22
• Subtask 7: 18 / 18