JavaSubstringComparisons.java

import java.util.Scanner;

public class Solution {

 public static String getSmallestAndLargest(String s, int k) {
 String smallest = "";
 String largest = "";
 
 // Complete the function
 // 'smallest' must be the lexicographically smallest substring of length 'k'
 // 'largest' must be the lexicographically largest substring of length 'k'
 
 smallest = s.substring(0,k);
 largest = s.substring(0,k);
 for(int i=0; i<=s.length()-k; i++ ){
 String str = s.substring(i,k+i);
 if (smallest.compareTo(str)>0){
 smallest = str;
 }
 if(largest.compareTo(str)<0){
 largest=str;
 }
 } 
 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));
 }
}