Java中条件语句和if-else的嵌套原则

 1 import java.util.Scanner;
 2 public class TestSum {
 3       /**
 4        * @param args
 5        */
 6       public static void main(String[] args) {
 7             // TODO Auto-generated method stub
 8         System.out.println("请输入分数");
 9             Scanner Sc=new Scanner(System.in);
10             int Score=Sc.nextInt();
11             
12             if(Score>=90){
13                   System.out.println("优");
14             }else if(Score>=70&&Score<90){
15             System.out.println("良");
16           }else if(Score>=60&&Score<70){
17           System.out.println("中");
18           }else{
19             System.out.println("差");
20           }
21       }
22 }