编写一个程序，从键盘读取字符，直到读取换行符“\n”

Question

编写一个程序，从键盘读取字符，直到读取换行符“\n”。然后让它打印元音的数量、辅音的数量、数字的数量和其他字符的数量。在其他字符的计数中包含最后换行字符。

我做了大多数操作，但当我键入时，它不会停止。谁能给我一些帮助吗？

import java.util.Scanner;
class characters{
  public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    int v=0;
    int c=0;
    int n=0;
    int o=0;
    char ch;
    do{
      System.out.println("Type in any characters: ");
      System.out.println("Type in \\n to stop. ");
      ch = scan.next().charAt(0);
      if(ch=='\n') {
        o++;
        break;}
      else
      {
        if('a'<=ch && ch<='z')
        {
          if(ch=='a') v++;
          else if(ch=='e') v++;
          else if(ch=='i') v++;
          else if(ch=='o') v++;
          else if(ch=='u') v++;          
          else c++;
        }
        else if('0'<=ch && ch<='9') n++;
        else o++;
      }

    }while(ch!='\n');
    System.out.println("There are "+v+" vowels, "+c+" consonants, "+n+" digits, and "+o+" other characters.");
  }
} 

Answer 1

“读取字符直到键入换行符”是一种非常奇特的说法“读取一行输入”。因此，只需读取整行输入，然后逐字符迭代即可获得您的计数。类似这样：

int v=0;
int c=0;
int n=0;
int o=0;
System.out.println("Enter a string of characters (Press ENTER when done):");
String line = scan.nextLine();

// OPTION 1 for iterating over the line character by character
for (char ch : line.toCharArray(){
    if ('a' <= ch && ch <= 'z')
        // etc...
}

// OPTION 2 for iterating over line
for (int i = 0; i < line.length(); ++i){
    char ch = line.charAt(i);
    if ('a' <= ch && ch <= 'z') 
         // etc...

}