蓝桥杯算法提高VIP-盾神与积木游戏

import java.util.Arrays;
import java.util.Comparator;
import java.util.Scanner;
public class 神盾与积木 {
    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
          Scanner scanner=new Scanner(System.in);
          int m=scanner.nextInt();
          for (int i = 0; i < m; i++) {
            int n=scanner.nextInt();
            Integer [][]dp=new Integer[n][2];
            for (int j = 0; j < n; j++) {
                dp[j][0]=scanner.nextInt();
                dp[j][1]=scanner.nextInt();
            }
            Arrays.sort(dp,new Comparator<Integer[]>() {
                @Override
                public int compare(Integer[] arg0, Integer[] arg1) {
                    // TODO Auto-generated method stub
                     return (arg0[1]-arg0[0])-(arg1[1]-arg1[0])>0?1:-1;
                }
            });
            int sum=0;boolean true1=true;
            for (int j = 0; j < dp.length; j++) {
                if (dp[j][0]+sum>=dp[j][1]) {
                    sum+=dp[j][0];
                }
                else {
                    true1=false;
                    break;
                }
            }
            if (true1) {
                System.out.println("YES");
            }
            else {
                System.out.println("NO");
            }
        }
    }
}