java - 我如何打印元音以及它们是什么？

Question

每次我输入句子时，它都会在每次循环时打印出结果。我假设我必须将打印行放在循环之外？

import java.util.*;
public class homework4{
public static void main(String[] args) {
//Scanner
Scanner keyBd = new Scanner(System.in);
System.out.println("Enter a sentence ");
String userIn = keyBd.nextLine();
  int count = 0;
  String empty= "";

  //Code
    for (int i = 0; i < userIn.length(); i++) {
           char ch = userIn.charAt(i);

        if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U') {
            count++;

                     System.out.println("There are " + count + " vowels in this string");

    }        
        if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U') {
            count++;
            empty += ch + " ";

                     System.out.println("The vowels are: " + empty);

    }
    }

    }
    }

Answer 1

import java.util.*;
public class homework4{
public static void main(String[] args) {
//Scanner
Scanner keyBd = new Scanner(System.in);
System.out.println("Enter a sentence ");
String userIn = keyBd.nextLine();
int count = 0;
String empty= "";

//Code
for (int i = 0; i < userIn.length(); i++) {
       char ch = userIn.charAt(i);

    if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u' || ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U') {
        count++;
        empty += ch + " ";                    
}
}
System.out.println("There are " + count + " vowels in this string");
System.out.println("The vowels are: " + empty);
}
}

无需检查两次状况。当您在循环中更新变量(count 和 empty)时，退出循环后只需打印一次。