為什么int score=53放在for循環里就錯誤了
public class HelloWorld {
??? public static void main(String[] args) {
???????
??????? // 變量保存成績
????????
???????
??????? // 變量保存加分次數
??????? int count = 0;
??????? //打印輸出加分前成績
????????? System.out.println("加分前成績:"+score);
??????
???????
??????? // 只要成績小于60,就循環執行加分操作,并統計加分次數
???????
????????? for(int score = 53;score<60;){
??????????? score=score+1;
??????????? count=count+1;
??????? }
??????? System.out.println("加分后成績:60");
??????? System.out.println("共加了"+count+"次!");
???????
???????
???????
???????
???????
??????? //打印輸出加分后成績,以及加分次數
?????
??? }
}
2020-03-07
作用域問題:
??for(int?score?=?53;score<60;)?//此處變量score作用域僅為?for循環內,當跳出?for?循環時,score會被回收 ??{???????????????????????????? ????????????score=score+1;??????? ????????????count=count+1; ??}?如下:
public?static?void?main(String[]?args)?{ ????int?count?=?0;????????//打印輸出加分前成績?????????? ????System.out.println("加分前成績:"+score);//?只要成績小于60,就循環執行加分操作,并統計加分次數????????????????? ????for(score?=?53;score<60;score++)?//此時為直接調用main方法中的變量score?,作用域為整個main方法 ????{???????????????????????? ???count?+=?1;???????? ????}???????? System.out.println("加分后成績:60");???????? System.out.println("共加了"+count+"次!"); }2020-03-01
可以放在for循環里呀,但是你12行寫了這句話
System.out.println("加分前成績:"?+?score);這句話前面沒定義score怎么能輸出去呢