Question

这是代码

Package labone;
import java.util.*;

public class LabOne {

static Scanner reader = new Scanner(System.in);
static ArrayList<String> names = new ArrayList<>();


public static void main(String[] args) {
    System.out.println("type\n 1: Exercise 1 'People's names'\n '");
    int choose = reader.nextInt();
    switch(choose) {
        case 1 :
            PeopleNames();
            break;
        default: 
            System.out.println("invaild choice");
            break;
    }         
}

  public static void PeopleNames() {                
       //////// PEOPLES NAMES ////////       
  System.out.println("Enter names of people, if done enter 'done'");
    String Name = reader.nextLine();
    while(!"done".equals(Name)){ //if user type done exit from adding names
        names.add(Name); // otherwise add names
        Name = reader.nextLine();  //reads what user entered
    }
    //User typed 'done' and it displays the names in the arraylist
    PrintArray(); // method

    //Find Longest String
  int largestString = names.get(0).length(); 
    int index = 0;
    for (int i = 0; i<names.size(); i++){
        if(names.get(i).length() > largestString) {
            largestString = names.get(i).length();
            index = i;
        }
    }
    System.out.println(names.get(index) + " is the longest name and the length is " + largestString);

    //Find Shortest String
   int shortestString = names.get(0).length();
    int index1 = 0;
     for (int i = 0; i<names.size(); i++){
        if(names.get(i).length() < shortestString) {
            shortestString = names.get(i).length();
            index1 = i;
        } 
    }
     System.out.println(names.get(index1) + " is the shortest name and the length is  " + shortestString); 

     //Find the Average of all the Strings
     double num = names.size(); //number of elements in arraylist(size())
     double length =-1; 
     for(String str : names){
         length = length + str.length(); //sum of the lengths in the arraylist 
     }   
     length = length + names.size()-1;   
      num = length/num;    //divide the sum with the size()
      System.out.println("The average length of the names in the list: "+num);
}


 //Method to view arrayList ( names )
public static void PrintArray() {
    System.out.println("---------");
    for(String Name : names){
        System.out.println(Name);
    }

  }
   }

结果运行：
类型 1：练习1'人名' 1
输入人名，如果完成输入'完成'
ashmeen
布洛姆
完成了

ashmeen是最长的名字，长度是7
是最短的名称，长度为0 不提供答案
列表中名称的平均长度：4.0
建立成功（总时间：12秒）

当我将代码放在main方法中时，它给出了最短字符串和最长字符串的答案，但是，当代码放在PeopleNames方法中时，它只显示最长的字符串，但它不显示最短的字符串。

Answer 1

请将reader.nextLine()更改为reader.next()，因为nextLine()函数正在向arrayList添加一个空字符串作为第一个成员。代码如下所示：

    String Name = reader.next();
    while(!"done".equals(Name)){ //if user type done exit from adding names
        names.add(Name); // otherwise add names
        Name = reader.next();  //reads what user entered
    }

问候。

最短字符串长度在main方法中显示，但在放入另一种方法时则不显示

1 个答案: