Question

Write a java program that will take a line of input and go through and print out that line again with all
the word numbers swapped with their corresponding numeric representations (only deal with numbers
from one to nine). Sample runs might look like this:
Please enter a line of input to process:
My four Grandparents had five grandchildren
My 4 grandparents had 5 grandchildren

without array and methods.

Answer 1

Below is your code:

import java.util.Scanner;

public class StringReplace {
        public static void main(String[] args) {
                // initializing Scanner object to get input from user
                Scanner sc = new Scanner(System.in);
                // Prompt user to take input from user
                System.out.println("Please enter a line of input to process:");
                // take complete line as input
                String line = sc.nextLine();

                // closing the scanner after taking input
                sc.close();

                // string has a replaceAll method which can replace
                // any substring to another substring
                // we can use the same for that
                // also if we add (?i) in front of the substring to be replaced
                // it will consider as case insensitive
                line = line.replaceAll("(?i)one", "1");
                line = line.replaceAll("(?i)two", "2");
                line = line.replaceAll("(?i)three", "3");
                line = line.replaceAll("(?i)four", "4");
                line = line.replaceAll("(?i)five", "5");
                line = line.replaceAll("(?i)six", "6");
                line = line.replaceAll("(?i)seven", "7");
                line = line.replaceAll("(?i)eight", "8");
                line = line.replaceAll("(?i)nine", "9");

                // printing the result
                System.out.println(line);

        }
}

Output

Please enter a line of input to process:
My four Grandparents had five grandchildren
My 4 Grandparents had 5 grandchildren