Submission #385792

#	Time	Username	Problem	Language	Result	Execution time	Memory
385792		SansPapyrus683	Global Warming (CEOI18_glo)	Java	100 / 100	500 ms	39312 KiB

glo

import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.*;

public class glo {
    public static void main(String[] args) throws IOException {
        BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer initial = new StringTokenizer(read.readLine());
        int tempNum = Integer.parseInt(initial.nextToken());
        int maxCheating = Integer.parseInt(initial.nextToken());
        int[] temps = Arrays.stream(read.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();

        int[] prefLongest = new int[tempNum];
        ArrayList<Integer> minEndings = new ArrayList<>();
        for (int i = 0; i < tempNum; i++) {
            int t = temps[i];
            int pos =  bisectLeft(minEndings, t);
            prefLongest[i] = pos + 1;
            if (pos == minEndings.size()) {
                minEndings.add(t);
            } else {
                minEndings.set(pos, t);
            }
        }

        int longest = 0;
        ArrayList<Integer> maxBegins = new ArrayList<>();
        for (int i = tempNum - 1; i >= 0; i--) {
            int t = temps[i];
            int pos = bisectLeft(maxBegins, -t);
            longest = Math.max(longest, prefLongest[i] + pos);

            int insertPos =  bisectLeft(maxBegins, -t - maxCheating);
            if (insertPos == maxBegins.size()) {
                maxBegins.add(-t - maxCheating);
            } else {
                maxBegins.set(insertPos, -t - maxCheating);
            }
        }
        System.out.println(longest);
    }

    private static int bisectLeft(List<Integer> arr, int x) {
        int lo = 0;
        int hi = arr.size();
        while (lo < hi) {
            int mid = (lo + hi) / 2;
            if (arr.get(mid) < x) {
                lo = mid + 1;
            } else {
                hi = mid;
            }
        }
        return lo;
    }
}

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