杭电oj2037——今年暑假不AC（java实现）

package hduoj;

import java.util.Scanner;

public class hdoj_2037 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while(true){
            int count = sc.nextInt();
            if(count == 0) break;
            int[][] data = new int[count][2];
            for(int i = 0;i<count;++i){
                data[i][0] = sc.nextInt();
                data[i][1] = sc.nextInt();
            }//initialize
            bubble_2D_arr(data);
            int res = 0;
            int index = -1;
            for(int i = 0;i < data.length;++i){
                if(data[i][0]>=index){
                    ++res;
                    index = data[i][1];
                }
            }
            System.out.println(res);
        }
    }

    private static void bubble_2D_arr(int[][] arr){
        boolean flag = false;
        int len = arr.length;//get the line number
        for(int i = 0;i < len;++i){
            for(int j = 1;j < len - i;++j){
                if(arr[j-1][1] > arr[j][1]){
                    int temp1 = arr[j-1][0];
                    int temp2 = arr[j-1][1];
                    arr[j-1][0] = arr[j][0];
                    arr[j-1][1] = arr[j][1];
                    arr[j][0] = temp1;
                    arr[j][1] = temp2;
                    flag = true;
                }
            }
            if(!flag) break;//indicates the seq isn‘t change ever before
        }
    }
}