java - 如何将用户输入的数组相乘？

Question

我正在编写一个程序，要求用户输入数组的长度，然后询问数组的元素。我的问题是如何将这些元素相乘？例如:数组的长度是多少？:4数组的元素是什么？: 3 6 4 7{3 6 4 7} 的乘法是 504。这是到目前为止我的代码:

     Scanner s = new Scanner(System.in);
     System.out.println("The length of your array is: ");
     int length = s.nextInt();
     int [] myArray = new int [length];
     System.out.println("The elements of your array are: ");

     for(int i=0; i<length; i++ ) {
        myArray[i] = s.nextInt();
     }

     System.out.printf("The multiplication of {%s} is ",Arrays.toString(myArray));

  }
} 

如有任何帮助，我们将不胜感激。

Answer 1

Scanner s = new Scanner(System.in);
    System.out.println("The length of your array is: ");
    int length = s.nextInt();    
    System.out.println("The elements of your array are: ");
long product = 1;
    for (int i = 0; i < length; i++) {
      product *= s.nextInt();
    }

    System.out.printf("The multiplication of {%s} is ", product);

稍微调整更新了您的代码

替代使用 lambda:

Scanner s = new Scanner(System.in);
List<Integer> numbers = new ArrayList();
System.out.println("The length of your array is: ");
int length = s.nextInt();    
System.out.println("The elements of your array are: ");


numbers = IntStream.range(0, length)
.mapToObj(i -> Integer.valueOf(s.nextInt()))
.collect(Collectors.toList());

System.out.printf("The multiplication of {%s} is {%s}",numbers, 
numbers.parallelStream()
.reduce(1, 
(number, product) -> product * number));