Submission #870812

#	Time	Username	Problem	Language	Result	Execution time	Memory
870812		salmon	Sequence (APIO23_sequence)	C++17	100 / 100	772 ms	70792 KiB

sequence

#include "sequence.h"

#include <bits/stdc++.h>
using namespace std;
int N;
int miin[500100 * 4];
int maax[500100 * 4];
int lazy[500100 * 4];
int miin1[500100 * 4];
int maax1[500100 * 4];
int lazy1[500100 * 4];
vector<int> in[500100];
vector<int> sat;

void build(int i, int s, int e, int *miin, int *maax, int *lazy){
    miin[i] = - e - 1;
    maax[i] = - s - 1;
    lazy[i] = 0;

    if(s != e){
        int m = (s + e + 2)/2 - 1;

        build(i * 2, s, m, miin, maax, lazy);
        build(i * 2 + 1, m + 1, e, miin, maax, lazy);
    }
}

void update(int i, int s, int e, int S, int *miin, int *maax, int *lazy){
    if(S <= s){
        miin[i] += 2;
        maax[i] += 2;
        lazy[i] += 2;
        return;
    }

    int m = (s + e + 2)/2 - 1;

    update(i * 2 + 1, m + 1, e, S, miin, maax, lazy);
    if(S <= m){
        update(i * 2, s, m, S, miin, maax, lazy);
    }

    miin[i] = min(miin[i * 2], miin[i * 2 + 1]) + lazy[i];
    maax[i] = max(maax[i * 2], maax[i * 2 + 1]) + lazy[i];
}

pair<int,int> query(int i, int s, int e, int S, int E, int *miin, int *maax, int *lazy){
    if(S <= s && e <= E){
        return make_pair(miin[i],maax[i]);
    }

    int m = (s + e + 2)/2 - 1;

    pair<int,int> ii,ii1;

    if(S <= m && m < E){
        ii = query(i * 2, s, m, S, E, miin, maax, lazy);
        ii1 = query(i * 2 + 1, m + 1, e, S, E, miin, maax, lazy);

        ii.first = min(ii.first, ii1.first) + lazy[i];
        ii.second = max(ii.second, ii1.second) + lazy[i];
    }
    else if(S <= m){
        ii = query(i * 2, s, m, S, E, miin, maax, lazy);

        ii.first = ii.first + lazy[i];
        ii.second = ii.second + lazy[i];
    }
    else{
        ii = query(i * 2 + 1, m + 1, e, S, E, miin, maax, lazy);

        ii.first = ii.first + lazy[i];
        ii.second = ii.second + lazy[i];
    }

    return ii;
}

int sequence(int N, std::vector<int> lst) {
    for(int i = 0; i < N; i++){
        in[lst[i]].push_back(i);
    }

    build(1,-1,N-1,miin1,maax1,lazy1);
    build(1,-1,N-1,miin,maax,lazy);

    bool flag = false;

    int ans = 0;

    for(int i = 1; i <= N; i++){
        sat.clear();

        sat.push_back(-1);
        for(int j = 0; j < in[i].size(); j++){
            sat.push_back(in[i][j]);
        }
        sat.push_back(N);

        for(int j = 0; j < in[i].size() ; j++){
            update(1,-1,N-1,in[i][j],miin,maax,lazy);
        }

        for(int j = 1; j <= in[i].size(); j++){

            int small = query(1, -1, N - 1, -1, sat[j] - 1, miin, maax, lazy).first;
            int big1 = query(1, -1, N - 1, -1, sat[j] - 1, miin1, maax1, lazy1).second;

            int l,r,m,s,e;
            int eye;

            eye = 1;
            l = sat[j];
            r = N - 1;

            s = -1;
            e = N - 1;

            int lacy = 0;
            int lacy1 = 0;

            while(s != e){
                m = (s + e)/2;

                lacy += lazy[eye];
                lacy1 += lazy1[eye];

                if(m < l){
                    s = m + 1;
                    eye = eye * 2 + 1;
                    continue;
                }

                if((maax[eye * 2 + 1] + lacy - small) * (long long int)(miin1[eye * 2 + 1] + lacy1 - big1) <= 0){
                    s = m + 1;
                    eye = eye * 2 + 1;
                    continue;
                }
                else{
                    e = m;
                    eye = eye * 2;
                }
            }

            auto it = upper_bound(sat.begin(),sat.end(),s);
            it--;

            ans = max(ans,(int)(it - sat.begin()) - j + 1);
       }

        for(int j = 0; j < in[i].size() ; j++){
            update(1,-1,N-1,in[i][j],miin1,maax1,lazy1);
        }
    }

    return ans;

}

Compilation message (stderr)

sequence.cpp: In function 'int sequence(int, std::vector<int>)':
sequence.cpp:95:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   95 |         for(int j = 0; j < in[i].size(); j++){
      |                        ~~^~~~~~~~~~~~~~
sequence.cpp:100:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |         for(int j = 0; j < in[i].size() ; j++){
      |                        ~~^~~~~~~~~~~~~~
sequence.cpp:104:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  104 |         for(int j = 1; j <= in[i].size(); j++){
      |                        ~~^~~~~~~~~~~~~~~
sequence.cpp:109:19: warning: variable 'r' set but not used [-Wunused-but-set-variable]
  109 |             int l,r,m,s,e;
      |                   ^
sequence.cpp:151:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  151 |         for(int j = 0; j < in[i].size() ; j++){
      |                        ~~^~~~~~~~~~~~~~
sequence.cpp:87:10: warning: unused variable 'flag' [-Wunused-variable]
   87 |     bool flag = false;
      |          ^~~~

• 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