convention2.txt

import java.io.*;
import java.util.*;

public class convention2 {
    public static void main(String[] args) throws IOException {
        BufferedReader f = new BufferedReader(new FileReader("convention2.in"));
        PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("convention2.out")),true);
        int cowsnum = Integer.parseInt(f.readLine());
        int[][] cows = new int[cowsnum][3];
        for(int i=0; i<cowsnum; i++){
            StringTokenizer st = new StringTokenizer(f.readLine());
            cows[i][0]=cowsnum-i;
            cows[i][1]=Integer.parseInt(st.nextToken());
            cows[i][2]=Integer.parseInt(st.nextToken());
        }
        PriorityQueue<int[]> queue = new PriorityQueue<>(new Comparator<int[]>() {
            @Override
            public int compare(int[] ints, int[] t1) {
                return -1*Integer.compare(ints[0],t1[0]);
            }
        });

        Arrays.sort(cows, new Comparator<int[]>() {
            @Override
            public int compare(int[] ints, int[] t1) {
                return Integer.compare(ints[1],t1[1]);
            }
        });
        int index=0;
        int time = cows[0][1];

        ArrayList<Integer> delay = new ArrayList<>();
        while (index<cowsnum && time>=cows[index][1]){
            queue.add(cows[index]);
            index++;
        }
        while(queue.size()>0){

                int[] curr = queue.poll();


                delay.add(time - curr[1]);
                time = time + curr[2];


            while (index<cowsnum&&time>=cows[index][1]){
                queue.add(cows[index]);
                index++;

            }
            if(queue.size()==0&&index<cowsnum){
                time=cows[index][1];

            }
            while (index<cowsnum&&time>=cows[index][1]){
                queue.add(cows[index]);
                index++;
            }


        }

        out.println(Collections.max(delay));
        out.close();


    }
}