Question

我需要一些帮助来解决如何处理一个java程序，该程序允许用户分别输入3个不同的字母，并告诉他们是否在一个设置的单词中，如果是，则在什么索引处。这是介绍，所以它应该是你专家的小菜一碟。我们没有关于这一部分的说明，所以我真的很难过。我们所知道的只是基本字符串。到目前为止，我有。

    import java.util.Scanner;

    public class guessletter {
        public static void main(String[] args) {
            Scanner scan = new Scanner(System.in);
            String name = "carson";
            int namelength = name.length();
            System.out.println("The name is "+namelength+" charecters long");
            System.out.println("Please enter a letter to guess?");
            String letter1 = scan.nextLine();   
            System.out.println("Please enter a letter to guess?");
            String letter2 = scan.nextLine();   
            System.out.println("Please enter a letter to guess?");
            String letter3 = scan.nextLine();   
        }   
    }

更新：忘记提及用户必须能够在最后猜出这个词以确定它们是否正确。我想我已经把它弄下来，但它说正确的名字是错误的。

import java.util.Scanner;

public class guessletter
{
    public static void main(String[] args) 
    {

    Scanner scan = new Scanner(System.in);
    String name = "carson";
    String name2;
    int namelength = name.length();
    System.out.println("The name is "+namelength+" charecters long");

    System.out.println("Please enter a letter to guess?");
    char letter = scan.nextLine().charAt(0);  // Gets the first character in the input  
    checkLetter(name, letter);

    System.out.println("Please enter a letter to guess?");
    letter = scan.nextLine().charAt(0);  
    checkLetter(name, letter); 

    System.out.println("Please enter a letter to guess?");
    letter = scan.nextLine().charAt(0);   
    checkLetter(name, letter);
    System.out.println("Please guess what the name is.");
    name2= scan.nextLine();
    if (name2 == name)
         System.out.println("Yes that is the name");
    else
         System.out.println("Nope, that is not the name");
    System.out.println("The name is "+name+"");

    }   

    public static void checkLetter(String name, char letter)
    {
    int indexOfLetter = name.indexOf(letter);
    if (indexOfLetter == -1)
        System.out.println("That letter isn't found in the name");
    else
        System.out.println("That Letter is in name. It is located at index " + (indexOfLetter+1));
    }

}

Answer 1

注意用户不一定只输入一个字母。您应该考虑这一点并仅测试输入字符串的第一个字符。

一种可能的方法如下：

在此代码中，您只使用.charAt(0)扫描每个输入字符串中的第一个字符（根据需要），然后使用.indexOf(letter)上的name方法测试它是否在字符串中根据需要变量。

import java.util.Scanner;

public class guessletter
{
    public static void main(String[] args) 
    {

    Scanner scan = new Scanner(System.in);
    String name = "carson";
    int namelength = name.length();
    System.out.println("The name is "+namelength+" charecters long");

    System.out.println("Please enter a letter to guess?");
    char letter = scan.nextLine().charAt(0);  // Gets the first character in the input  
    checkLetter(name, letter);

    System.out.println("Please enter a letter to guess?");
    letter = scan.nextLine().charAt(0);  
    checkLetter(name, letter); 

    System.out.println("Please enter a letter to guess?");
    letter = scan.nextLine().charAt(0);   
    checkLetter(name, letter);

    }   

    public static void checkLetter(String name, char letter)
    {
    int indexOfLetter = name.indexOf(letter);
    if (indexOfLetter == -1)
        System.out.prinln("Letter is not in name");
    else
        System.out.println("Letter is in name! index is " + (indexOfLetter+1));
    }

}

Answer 2

使用方法 String #indexOf ，如果给定的char不在单词中，则方法返回-1。

   String name = "carson";
   System.out.println(name.indexOf("a"));
   System.out.println(name.indexOf("z"));

Answer 3

这将为您完成工作，

import java.util.Scanner;

    public class guess
    {
        public static void main(String[] args) 
        {
      Scanner scan = new Scanner(System.in);
        String name = "carson";
        int namelength = name.length();
        int l=3;
        String letter;
        System.out.println("The name is "+namelength+" charecters long");
        while(l-->0){
        System.out.println("Please enter a letter to guess?");
         letter= scan.nextLine(); 
         if(name.indexOf(letter)!=-1){
            System.out.println("Letter found at position "+(name.indexOf(letter)+1));
         }else{
            System.out.println("Letter not found");
         }
        }

    }    

  }

Answer 4

您也可以使用.contains for Strings

if(name.contains("a")){
//code
}

Java程序，让用户猜3个字母，以猜出一个名字？

4 个答案: