Question

我正在开发一个简单的程序来确定用户的输入是否是一个8字符的预定义数组。如果是，则应打印出字母及其位置。如果没有，它应该说它不存在。

问题在于它通过数组查找并找到该字符，然后转到其他地方并打印出它并不知道＆＃34;由于for循环，它在7个剩余位置的位置。我在纸上追踪变量和条件，虽然我有点理解为什么会出现问题，但我真的不知道如何解决它。

到目前为止，我已经尝试打破循环，创建一个布尔值，如果找到该角色就会改变并打印出来的信息（仍然是它的问题转移到其他地方并打印7次，它可以＆＃39 ;找到它。）

char search;
char tryAgain='Y';
char arrayChar[]= {'a', 'd', 'g', 'h', 'r', 't', 'u', 'y'};

while(tryAgain == 'Y')//while user enters Y
{   
    System.out.println("\nEnter a character to check if it is present in the array");
    search= input.nextLine().charAt(0);//extract first letter

    for(int i = 0; i < arrayChar.length; i++)//looks through
    {   
        if(search == arrayChar[i])//if it is found      
            System.out.println(search + " was found in the " + i +" position\n");//print that it is
        else
            System.out.println("Cannot find the character");
    }

    System.out.println("Would you like to try again? Yes/No?");
    tryAgain= input.nextLine().charAt(0);
}//while try again

System.out.println("Thank you come again");

Answer 1

完成循环后，只需打印Cannot find即可。像这样：

import java.io.*;
import java.util.*;
import java.lang.*;

class Example
{
    public static void main(String args []){
        char search;
        Scanner input = new Scanner(System.in);
        System.out.println("Enter the first number");
        //get user input for a
        char tryAgain='Y';

        char arrayChar[]= {'a', 'd', 'g', 'h', 'r', 't', 'u', 'y'};


        while(tryAgain == 'Y')//while user enters Y
        {   
            boolean verify = false;
            System.out.println("\nEnter a character to check if it is present in the array");
            search= input.nextLine().charAt(0);//extract first letter

            for(int i = 0; i < arrayChar.length; i++)//looks through
            {   

                if(search == arrayChar[i])//if it is found      
                {
                    verify = true;
                    System.out.println(search + " was found in the " + i +" position\n");//print that it is
                }


            }
            if(verify == false){
                System.out.println("Cannot find the character");
            }
            System.out.println("Would you like to try again? Yes/No?");
            tryAgain= input.nextLine().charAt(0);


        }//while try again

        System.out.println("Thank you come again"); 
    }
}

Answer 2

你需要将else语句放在for循环之外，因为每次它通过for语句中的“i”查找并且找不到该字符时它将打印“else”，所以“else”应该是那样：

  for(int i = 0; i < arrayChar.length; i++) {  

      if(search == arrayChar[i])    

            System.out.println(search + " was found in the " + i +" position\n");
    }       
      else 
                System.out.println("Cannot find the character");

Answer 3

1）你的“其他”是在错误的地方，

2）你可以使用“for（）”循环中的“break”：

    char search;
    char tryAgain='Y';
    char arrayChar[]= {
      'a', 'd', 'g', 'h', 'r', 't', 'u', 'y'
    };

    //while user enters Y  
    do { 
      System.out.println("\nEnter a character to check if it is present in the array");
      search= input.nextLine().charAt(0);//extract first letter

      //looks through
      boolean found = false;
      for(int i = 0; i < arrayChar.length; i++)h {   
        if(search == arrayChar[i]) {  
          System.out.println(search + " was found in the " + i +" position\n");
          found = true;
          break;
        }
      } 

      if (!found) {
        System.out.println("Cannot find the character");
      }

      System.out.println("Would you like to try again? Y/N?");
      tryAgain= input.nextLine().charAt(0);

    } while(java.lang.Character.toUpperCase(tryAgain) == 'Y');

    System.out.println("Thank you come again");
  }

Answer 4

如果我明白了，你是否需要在找到它时停止内部循环，或者如果不理解则继续？

试试这个：

    char search;
    char tryAgain = 'Y';
    char arrayChar[] = { 'a', 'd', 'g', 'h', 'r', 't', 'u', 'y' };
    boolean found = false;
    int position = 0;

    while (tryAgain == 'Y')// while user enters Y
    {
        System.out
                .println("\nEnter a character to check if it is present in the array");
        search = input.nextLine().charAt(0);// extract first letter

        found = false;
        position = 0;

        for (int i = 0; i < arrayChar.length; i++)// looks through
        {
            if (search == arrayChar[i]) { // if it is found
                found = true;
                position = i;
                break;
            }
        }

        if (found) {
            System.out.println(search + " was found in the " + position
                    + " position\n");// print that it is
            System.out.println("Would you like to play again? Yes/No?");
            tryAgain = input.nextLine().charAt(0);
        } else {
            System.out.println("Cannot find the character");
            System.out.println("Would you like to try again? Yes/No?");
            tryAgain = input.nextLine().charAt(0);
        }
    }// while try again

    System.out.println("Thank you come again");

.Ryan。

Answer 5

你的代码有很多错误，至少在我的电脑上是这样。你的＆＃34;其他＆＃34;声明是好的，但实施是错误的，这给了＆＃34;找不到＆＃34;在＆＃34; FOUND＆＃34;之后信，这是工作代码：

    import java.util.*;
    import java.io.*;
    import java.lang.*;;

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

    char search;
    Scanner input = new Scanner(System.in);
    char tryAgain='Y';
    char[] arrayChar = new char[] { 'a', 'd', 'g', 'h', 'r', 't', 'u', 'y' };
    boolean flag = false;

while(tryAgain == 'Y')//while user enters Y
{   
System.out.println("\nEnter a character to check if it is present in the array");
    search= input.nextLine().charAt(0);

    for(int i = 0; i < arrayChar.length; i++) {  
        if(search == arrayChar[i])    {
            flag = true;
            System.out.println(search + " was found in the " + i +" position\n");
            break;

如果for循环找到了char，并且在它循环通过for循环之前，甚至在找到与其他char不匹配的char并转到else语句之后，你需要在这里打破，然后打印else语句你了。

        }
        else {  flag = false;   }
    }
    if(flag == false){
            System.out.println("Cannot find the character");
            //flag = true;
    }

    System.out.println("Would you like to try again? Y/N?");
        tryAgain = Character.toUpperCase(input.nextLine().charAt(0));
        //while user enters Y or y

}//while try again

System.out.println("Thank you come again");
    }
}

我怎样才能控制我的for循环

5 个答案: