Java program to check unique number

Sample Program:-

 import java.util.*;  
 import java.io.*;  
 /**  
  * Created by Dixit on 29-08-2017.  
  */  
 public class IsUniqueNumber {  
   public static boolean  
   isUniqueUsingHash(String word)  
   {char[] chars = word.toCharArray();  
     Set<Character> set = new HashSet<Character>();  
     for (char c : chars)  
       if (set.contains(c))  
         return false;  
       else {  
         set.add(c);  
       }  
     return true;  
   }  
   public static boolean  
   isUniqueUsingSort(String word)  
   {char[] chars = word.toCharArray();  
     if (chars.length <= 1)  
       return true;  
     Arrays.sort(chars);  
     char temp = chars[0];  
     for (int i = 1; i < chars.length; i++)  
     {if (chars[i] == temp)  
       return false;  
       temp = chars[i];  
     }  
     return true;  
   }  
   public static void main(String[] args)  
       throws IOException  
   {  
     System.out.println(isUniqueUsingHash("1234")? "Unique" : "Not Unique");  
         System.out.println(isUniqueUsingSort("123")? "Unique" : "NotUnique");  
   }  
 }  

Enjoy Coding