Submission #358609

#	Time	Username	Problem	Language	Result	Execution time	Memory
358609		sumit_kk10	Global Warming (CEOI18_glo)	C++14	10 / 100	2089 ms	4072 KiB

glo

#include <bits/stdc++.h>
#define fast ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL)
using namespace std;
const long long int N = 1e6 + 5;
const long long int MOD = 1e9 + 7;

int main(){
    fast;
    long long int n, x;
    cin >> n >> x;
    long long int a[n];
    for(long long int i = 0; i < n; ++i)
        cin >> a[i];    
    vector<pair<long long int, long long int> > lis;
    lis.push_back({a[0], 0});
    for(long long int i = 1; i < n; ++i){
        if(a[i] > lis.back().first){
            lis.push_back({a[i], i});
            continue;
        }
        long long int low = 0, high = lis.size() - 1, ans = -1;
        while(low <= high){
            long long int mid = (low + high) / 2;
            if(lis[mid].first >= a[i]){
                ans = mid;
                high = mid - 1;
            }
            else
                low = mid + 1;
        }
        if(ans == -1)
            continue;
        lis[ans] = {a[i], i};
    }
    if(x == 0){
        cout << lis.size() << '\n';
        return 0;
    }
    int mx = lis.size();
    lis.push_back({0, 0});
    lis.push_back({INT_MAX, n - 1});
    sort(lis.begin(), lis.end());
    for(int i = 1; i < lis.size(); ++i){
        int r = lis[i].second, l = lis[i - 1].first;
        for(int j = l; j <= r; ++j)
            a[j] += x;
        vector<long long int> lis1;
        lis1.push_back(a[0]);
        for(int j = 1; j < n; ++j){
            if(a[j] > lis1.back()){
                lis1.push_back(a[j]);
                continue;
            }
            int low = 0, ans = -1, high = lis1.size();
            while(low <= high){
                int mid = (low + high) / 2;
                if(lis1[mid] >= a[j]){
                    ans = mid;
                    high = mid - 1;
                }
                else
                    low = mid + 1;
            }
            if(ans == -1) continue;
            lis1[ans] = a[j];
        }
        mx = max(mx, (int) lis1.size());
        for(int j = l; j <= r; ++j)
            a[j] -= 2*x;
        lis1.clear();
        lis1.push_back(a[0]);
        for(int j = 1; j < n; ++j){
            if(a[j] > lis1.back()){
                lis1.push_back(a[j]);
                continue;
            }
            int low = 0, ans = -1, high = lis1.size();
            while(low <= high){
                int mid = (low + high) / 2;
                if(lis1[mid] >= a[j]){
                    ans = mid;
                    high = mid - 1;
                }
                else
                    low = mid + 1;
            }
            if(ans == -1) continue;
            lis1[ans] = a[j];
        }
        mx = max(mx, (int) lis1.size());
        for(int j = l; j <= r; ++j)
            a[j] += x;
    }
    cout << mx << '\n';
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int main()':
glo.cpp:43:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |     for(int i = 1; i < lis.size(); ++i){
      |                    ~~^~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 13
• Subtask 4: 10 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 17
• Subtask 7: 0 / 25