Need to print a string array

Question

My task is to read the strings by input, and then display the strings that have more than 4 vowels in each. I have this code:


import java.util.Scanner;
public class Main {
    static boolean vowelChecker(char a) {
        a = Character.toLowerCase(a);
        return (a=='a' || a=='e' || a=='i' || a=='o' || a=='u' || a=='y');
    }
    static int counter(String str) {
        int count = 0;
        for (int i = 0; i < str.length(); i++)
            if (vowelChecker(str.charAt(i))) {
                ++count;
            }
        return count;
    }
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the number of elements you want to store: ");
        int n;
        n=scanner.nextInt();
        String[] array = new String[100];
        System.out.println("Enter the elements of the array: ");
        for(int i=0; i<n; i++)
        {
            array[i]=scanner.nextLine();
        }
        String str = scanner.nextLine();
        int b = counter(str);
        if (b > 4) {
            System.out.println("What do I write here?");
        }
    }
}

And my question is: how to correctly write the code so that the output would be strings from input that have more than 4 vowels?

Why do you read strings into `array` but never use them? – tgdavies Dec 29 '21 at 01:39 — tgdavies, Dec 29 '21 at 01:39

Chrimle · Answer 1 · 2021-12-29T02:16:17.870

1

Like others have pointed out, you never read from the array. Read for each of the strings, if the counter() returns a value larger than 4, we want to print it. So, this could do the trick:

for(int i=0; i<n; i++)
{
  if (counter(array[i]) > 4)
    System.out.println(array[i]);
}

Using nextInt won't absorb the newline character \n, that's why you are inputting 1 string less. There are some workarounds that you can read about here.

edited Dec 29 '21 at 02:16

answered Dec 29 '21 at 01:51

Chrimle

490
1
4
10

thank you, that worked! i also wanted to ask, i have a problem with entering the amount of strings. for example, i type 5, but then after i enter 4 strings it's already over. how to improve my code? – Dec 29 '21 at 02:00
This is because you use `nextInt`. It keeps the "enter" that you press in the scanner. The first `scanner.nextLine();` reads it before you can ever type anything in. Then, you get to type in your 4 strings (5-1). – Chrimle Dec 29 '21 at 02:18

score 1 · Answer 2 · answered Dec 29 '21 at 01:54

import java.util.Scanner;

public class Test {
    private static final char[] VOWELS = new char[]{'a', 'e', 'i', 'o', 'u', 'y'};

    public static void main(String[] args) {
        // Initialize and open a new Scanner
        final Scanner scanner = new Scanner(System.in);

        // Get the number of lines we want to analyze
        System.out.print("Enter the number of elements you want to store: ");
        final int n = Integer.parseInt(scanner.nextLine());

        // Get all the lines from the user
        System.out.println("Enter the elements of the array: ");
        final String[] lines = new String[n];
        for(int i = 0; i < n; i++) {
            lines[i]=scanner.nextLine();
        }

        // Close the Scanner
        scanner.close();

        // Check each line, count the number of vowels, and print the line if it has more than 4 vowels.
        System.out.println("\nInputs that have more than 4 vowels");
        for(int i = 0; i < n; i++) {
            if (countVowels(lines[i]) > 4) {
                System.out.println(lines[i]);
            }
        }
    }

    private static boolean isVowel(char a) {
        for (int i = 0; i < VOWELS.length; i++) {
            if (Character.toLowerCase(a) == VOWELS[i]) {
                return true;
            }
        }
        return false;
    }

    private static int countVowels(final String str) {
        int count = 0;
        for (int i = 0; i < str.length(); i++) {
            if (isVowel(str.charAt(i))) {
                count++;
            }
        }
        return count;
    }
}

Austngmnz · Accepted Answer · 2021-12-29T02:46:32.503

0

So this first part makes sense :

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    System.out.print("Enter the number of elements you want to store: 
    ");
    int n;
    n=scanner.nextInt();
    String[] array = new String[100];
    System.out.println("Enter the elements of the array: ");
    for(int i=0; i<n; i++)
    {
        array[i]=scanner.nextLine();
    }

after this part I would just do :

for (String s: array) {
if (Objects.isNull(s))
    break;
 if (count(s) >= 5) {
System.out.println(s);
}
}

edited Dec 29 '21 at 02:46

answered Dec 29 '21 at 02:04

Austngmnz

24
2

true, in my head I was thinking 4 or more when i wrote it. i changed it to a 5 to match the request. – Austngmnz Dec 29 '21 at 02:09
Indexes begins from 0. So if you have `i<=n`, it could result in a `IndexOutOfBoundsException`. If you enter `1`. You will have to enter 2 strings: string 0 and string 1. – Chrimle Dec 29 '21 at 02:13

steven7mwesigwa · Answer 4 · 2021-12-29T03:18:46.247

import java.util.Arrays;
import java.util.Objects;
import java.util.Scanner;

class Main {

    static long counter(String str) {

        return Arrays.stream(str.split(""))
                .filter(c -> Arrays.asList("a", "e", "i", "o", "u", "y").contains(c.toLowerCase()))
                .count();
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the number of elements you want to store: ");
        int n;
        n = scanner.nextInt();
        scanner.nextLine();

        String[] array = new String[n];

        System.out.println("Enter the elements of the array: ");

        for (int i = 0; i < n; i++) {
            String str = scanner.nextLine();

            if (counter(str) > 4) {
                array[i] = str;
            }
        }

        System.out.println(Arrays.toString(Arrays.stream(array).filter(Objects::nonNull).toArray(String[]::new)));
    }
}

Need to print a string array

4 Answers4