Convert integer from 0-10 and replace with English word that corresponds to integer

Question

Here in this code when 10 occurs in the input it is printing one zero instead of printing ten.

How can I resolve this problem?

import java.util.Scanner;

public class Program {
    public static void main(String[] args) {
        Scanner scn = new Scanner(System.in);
        String phrase = scn.nextLine();
        String[] digits = {"0","1","2","3","4","5","6","7","8","9","10"};
        String[] alphabets = {"zero","one","two","three","four","five","six","seven","eight","nine","ten"};
        for (int i=0; i<digits.length; i++) {
            phrase = phrase.replaceAll(digits[i],alphabets[i]+"");
        }
        System.out.println(phrase);
    }
}

Answer 1

Ten is the first "digit" that is actually two digits. You change zero and one first. Change ten first instead to handle that case, (or you could make it A instead of "10" - you seem to have base eleven here).

String[] digits = { "10", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9" };
String[] alphabets = { "ten", "zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine" };

Answer 2

This is because of incorrect iteration method, you need to iterate in reverse.

    public class Sample {
public static void main(String[] args) {
    Scanner scn = new Scanner(System.in);
    String phrase = scn.nextLine();
    String[] digits = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "10"};
    String[] alphabets = {"zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten"};
    for (int i = digits.length - 1; i >= 0; i--) {
        phrase = phrase.replaceAll(digits[i], alphabets[i] + "");
    }
    System.out.println(phrase);
}

}

Answer 3

Your problem is that you process each character in the input, probably without spaces, instead of "words" separated by spaces.

You can split the input into words by doing String[] numbers = phrase.split(" ");, and then create a new return string with each number replaced by the corresponding word.

You should probably use a hashmap instead of two arrays as well.

Answer 4

A workaround : Replace "onezero" with "ten".

Demo:

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scn = new Scanner(System.in);
        String phrase = scn.nextLine();
        String[] digits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "10" };
        String[] alphabets = { "zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten" };
        for (int i = 0; i < digits.length; i++) {
            phrase = phrase.replace(digits[i], alphabets[i]).replace("onezero", "ten");
        }
        System.out.println(phrase);
    }
}

A sample run:

hello10world
hellotenworld

Note that you should use replace instead of replaceAll which is used with regex.