字符串数组的长度之和[duplicate]

Question

我希望用户首先选择要键入的单词数，然后将单词数相加（例如Hello and bye=5 3=所有行的总长度为8），但我不知道如何将数组中的所有元素相加。

我的代码：

import java.util.Scanner;

public class StringLengthSum {
  public static void main(String[] args) {
      
    Scanner sc = new Scanner(System.in);
    int index;
    int limit;
    int sum;
    String[] data;

    System.out.println("Number of text lines:");
    limit = Integer.parseInt( sc.nextLine() );
    data = new String [limit];

    System.out.println("Text lines:");
    index=0;
    while ( index < limit )
    {
      data[index] = sc.nextLine();
      index=index+1;
    }

    System.out.println("Given input:");
    index = 0;
    while ( index < limit )
    {
      System.out.println("Line " + index + ": " + data[index]);
      index = index + 1;
    }

    index = 1;
    while ( index < limit )
    {
      System.out.println("Total length of all lines is " + data[index].length() + "." );
      index = index + 1;
    }

谢谢你的帮助

Answer 1

感谢您提出关于单词数组长度求和的问题。您可以通过在数组上映射String::长度方法来做到这一点。请参阅jshell中的以下两行：

jshell> var words = new String[] {"mouse", "cat", "dog"};
words ==> String[3] { "mouse", "cat", "dog" }

jshell> Arrays.stream(words).mapToInt(String::length).sum();
$2 ==> 11