백준 - 1931 회의실 배정 (feat. java)

import java.util.Arrays;
import java.util.Comparator;
import java.util.Scanner;

public class Main {
	static int[][] conference;
	static int N;
	static int K;
	
	
	public static void main(String[] args) {
		
		Scanner sc = new Scanner(System.in); 
		
		N = sc.nextInt();
		conference = new int[N][2];
		
		for (int i = 0; i < N; i++) {
			for (int j = 0; j < 2; j++) {
				conference[i][j] = sc.nextInt();
			}
		}
		
		Arrays.sort(conference, new Comparator<int[]>() {

			@Override
			public int compare(int[] arr1, int[] arr2) {
				
				if (arr1[1] == arr2[1]) {
					return arr1[0] - arr2[0];
				} else {
					return arr1[1] - arr2[1];
				}
			}
			
		});
		
		int end		= 0;
		int result	= 0;
		
		for (int i = 0; i < N; i++) {
			if (conference[i][0] >= end) {
				end = conference[i][1];
				result++;
			}
		}

		System.out.println(result);
	}
}