In this HackerRank java substring comparisons problem in the java programming language you have Given a string, s, and an integer, k, complete the function so that it finds the lexicographically smallest and largest substrings of length k.

HackerRank Java Substring Comparisons problem solution


HackerRank java substring comparisons problem solution.

import java.util.Scanner;

public class Solution {

    public static String getSmallestAndLargest(String s, int k) {
        String smallest = "";
        String largest = "";
        
        java.util.List<String> a = new java.util.ArrayList<>();

        for(int i=0;i<s.length()-k+1;i++){
                a.add(s.substring(i,i+k));   
        }
        java.util.Collections.sort(a);
         smallest = a.get(0);
         largest = a.get(a.size()-1);
        return smallest + "\n" + largest;
    }


    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String s = scan.next();
        int k = scan.nextInt();
        scan.close();
      
        System.out.println(getSmallestAndLargest(s, k));
    }
}


Second solution

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        int k = scanner.nextInt();
        String minSubstring = line.substring(0,k);
        String maxSubstring = line.substring(0,k);
        for (int i = 1; i < line.length()-k+1; i++) {
            String sub = line.substring(i,i+k);
            if (sub.compareTo(minSubstring) < 0) {
                minSubstring = sub;
            }
            if (sub.compareTo(maxSubstring) > 0) {
                maxSubstring = sub;
            }
        }
        System.out.println(minSubstring);
        System.out.println(maxSubstring);
    }
}