一個簡單的Java方法不起作用

Question

大家好，我是Java編程語言的新手，並且一直在學習方法的使用，下面是我寫的用於將兩個數字相加的簡單方法，但是當我運行代碼時，它不顯示任何輸出，請我在做什么錯？ 在這種情況下，代碼的總和應為2到4

//testing Java methods
    public class Methods {
       public static void main(String [] args) {
         int addition = add (2,4);
         System.out.println(addition);
      }

//the method for addition
      public static int add(int a, int b){
         int sum = 0;
         for (int i = a; a <= b ; i++)
           sum += i;
        return sum;
    }
}

Answer 1

for (int i = a; a <= b ; i++)

它應該是

 for (int i = a; i <= b ; i++)

Answer 2

它實際上正在陷入無限循環 。

試試這個程序（從a <= b to i <= b ）

 public static void main(String[] args) {
        int addition = add(2, 4);
        System.out.println(addition);
    }

    // the method for addition
    public static int add(int a, int b) {
        int sum = 0;
        for (int i = a ; i <= b ; i++) {
            sum += i;
        }
        return sum;
    }

產量

9

Answer 3

你的for循環應該是

for (int i = a; i <= b ; i++)

Answer 4

//testing Java methods
public class Methods {
    public static void main(String[] args) {
        int addition = add(2,4);
        System.out.println(addition);
    }

    //the method for addition
    public int add(int a, int b){ // Place this method in the class.
        int sum = 0;
        for (int i = a; i <= b ; i++){ // "a <= b" Has to be: i <= b
            sum += i;
        }
        return sum;
    }
}

我想這就是你想要的。

結果將是：2 + 3 + 4 = 9