Justifying a string followed by a number

Question

I started practicing on HackerRank to see how my learning is going on with Java. I wrote this code for problem which involved input having:

1. String with maximum length of 10, followed by
2. A 3 digit or lesser integer

Examples: "java 100", "Amazing 98"

Expected output:

1. String should be left-justified with trailing white spaces till 15th character
2. Leading digit of integer starts at 16th place with leading zeroes if it is less than 3 digits(padding) to make up for 18 characters

Examples: "java 100", "Amazing 098"

package HackerRank;
import java.util.ArrayList;
import java.util.Scanner;
public class IOFormatting {
 public ArrayList<String> getAllLines(){
 ArrayList<String> allInputs = new ArrayList<String>();
 Scanner getIp = new Scanner(System.in);
 while(getIp.hasNext()) {
 allInputs.add(getIp.nextLine());
 }
 getIp.close();
 return allInputs;
 }
 public ArrayList<Character> getTheInputAsArrayList(String input) {
 ArrayList<Character> inputLine = new ArrayList<Character>();
 for(int itr1=0;itr1<input.length();itr1++) {
 inputLine.add(input.charAt(itr1));
 }
 return inputLine;
 }
 public ArrayList<Character> formatTheArrayList(ArrayList<Character> inputLine){
 int itr2 = getBreakPoint(inputLine);
 for(int itr3=itr2+1;itr3<15;itr3++) {
 inputLine.add(itr3,' ');
 }
 return inputLine;
 }
 public int getBreakPoint(ArrayList<Character> inputLine){
 for(int itr2=0;itr2<=10;itr2++) {
 if(inputLine.get(itr2) == ' ') {
 return itr2;
 }
 }
 return 0;
 }
 public ArrayList<Character> doIntegerPadding(ArrayList<Character> inputLine){
 int padSize = 18 - inputLine.size();
 if(padSize>0) {
 for(int itr4=15;itr4<=14+padSize;itr4++) {
 inputLine.add(itr4,'0');
 }
 }
 return inputLine;
 }
 public String convertToFinalString(ArrayList<Character> inputLine) {
 String outputString = "";
 StringBuffer sb = new StringBuffer();
 for (Character s : inputLine) {
 sb.append(s);
 }
 outputString = sb.toString();
 return outputString;
 }
 public static void main(String args[]) {
 IOFormatting io = new IOFormatting();
 ArrayList<String> allInputs = io.getAllLines();
 System.out.println("================================");
 for(int mainItr=0;mainItr<allInputs.size();mainItr++) {
 String input = allInputs.get(mainItr);
 ArrayList<Character> inputLine = io.getTheInputAsArrayList(input);
 inputLine = io.formatTheArrayList(inputLine);
 inputLine = io.doIntegerPadding(inputLine);
 String outputString = io.convertToFinalString(inputLine);
 System.out.println(outputString);
 }
 System.out.println("================================");
 }
}

Answer 1

You are vastly overcomplicating the solution. The Scanner is perfectly capable of reading a string and an integer separately. Then, it is a simple matter of calling System.out.printf() with the appropriate width specifications:

• %-15s for a string, left-justified, with trailing spaces
• %03d for an integer, zero-padded

Also, Scanner is AutoCloseable, so you should use a try-with-resources block instead of calling .close() on it manually.

import java.util.Scanner;
public class IOFormatting {
 public static void main(String[] args) {
 try (Scanner input = new Scanner(System.in)) {
 while (input.hasNext()) {
 System.out.printf("%-15s%03d%n", input.next(), input.nextInt());
 }
 }
 }
}

If you really wanted to do the formatting the hard way by inserting spaces and zeroes, I suggest editing each line using StringBuilder.insert() — your ArrayList<Character> is a rather unnatural way to edit a string.

• Akash Singh: Great!!, I've got new stuff to read. Moreover, I wanted someone to tell me what you just did : "Unnatural"