Question

我完成了这项任务。看着它，我觉得括号和if else语句的一切都很好。但是，错误表示＆＃34;缺少return statement}＆＃34;
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public class CompareNums {
    // TODO - write your code below this comment.
    // The method you define will return one of three possible strings:
    // - "less than": if the first parameter is less than the second
    // - "equal to": if the first parameter is equal to the second
    // - "greater than": if the first parameter is greater than the second
    // Make sure you return _exactly_ the above strings
    public static String comparison(int first, int second) {
        if (first<second) {
            return "less than"; 
        } else if (first==second) {
            return "equal to"; 
        } else if (first>second) {
            return "greater than";
        }
    }



    // DO NOT MODIFY main!
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("Enter first integer: ");
        int first = input.nextInt();
        System.out.print("Enter second integer: ");
        int second = input.nextInt();
        System.out.println("The first integer is " +
                           comparison(first, second) +
                           " the second integer.");
    }
}

Answer 1

如果您在函数内使用返回，则需要使用if结束else语句。错误基本上是说如果没有满足这些条件，仍然需要返回一些内容。使用您的示例，您可以这样说：

 public static String comparison(int first, int second) {
        if (first<second) {
            return "less than"; 
        } else if (first>second) {
            return "greater than";
        } else {
            return "equal to";
        }
    }

你可以假设，如果第一个不小于或大于第二个，则它等于。

Answer 2

if (first<second) {
            return "less than"; 
        } else if (first==second) {
            return "equal to"; 
        } else if (first>second) {
            return "greater than";
        }

最后else if是多余的，是问题的真正原因。自然如果以上两个条件都是假的，那么first将大于second。只需使用else代替else if。

if (first<second) {
            return "less than"; 
        } else if (first==second) {
            return "equal to"; 
        } else  {
            return "greater than";
        }

如果是的话。难以正确形成回报

2 个答案: