Submission #246340

#	Time	Username	Problem	Language	Result	Execution time	Memory
246340		Sorting	Global Warming (CEOI18_glo)	C++14	55 / 100	2070 ms	3052 KiB

glo

#include <bits/stdc++.h>

using namespace std;

const int k_N = 2e5 + 3;
const int k_Inf = 1e9 + 3;

int n, x;
int t[k_N];

int ans[k_N];

int get_lis(){
    vector<int> dp;
    dp.push_back({-k_Inf});

    for(int i = 0; i < n; ++i){
        auto it = lower_bound(dp.begin(), dp.end(), t[i]);
        if(it == dp.end())
            dp.push_back(t[i]);
        else
            dp[it - dp.begin()] = t[i];

        ans[i] += dp.size() - 1;
    }
    return dp.size() - 1;
}

void get_lds(){
    vector<int> dp;
    dp.push_back({k_Inf});

    for(int i = n - 1; i >= 0; --i){
        int l = 0, r = dp.size();
        while(l != r){
            int mid = (l + r) >> 1;
            if(t[i] >= dp[mid])
                r = mid;
            else
                l = mid + 1;
        }
        if(l == dp.size())
            dp.push_back(t[i]);
        else
            dp[l] = t[i];

        //cout << dp.size() << "\n";
        ans[i - 1] += dp.size() - 1;
    }
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    cin >> n >> x;
    for(int i = 0; i < n; ++i)
        cin >> t[i];

    if(x == k_Inf - 3){
        int answer = 0;
        get_lds();
        get_lis();

        for(int i = 0; i < n; ++i)
            answer = max(ans[i], answer);

        cout << answer << "\n";
    }
    else{
        int answer = 0;
        for(int i = 0; i < n; ++i){
            t[i] -= x;
            answer = max(get_lis(), answer);
            if(x == 0)
                break;
        }

        cout << answer << "\n";
    }
}

Compilation message (stderr)

glo.cpp: In function 'void get_lds()':
glo.cpp:42:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(l == dp.size())
            ~~^~~~~~~~~~~~

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