Question

How to print all elements of an array only once in Java

Answer 1

import java.util.HashMap; 

public class MyClass {
    static void printElementsOnlyOnce(int[] arr) { 
        HashMap<Integer,Integer> hm = new HashMap<Integer,Integer>(); 
            for (int i = 0; i < arr.length; i++) { 
                hm.put(arr[i], i); 
            } 
        System.out.println(hm.keySet()); 
    }
    public static void main(String args[]) {
      int[] arr = {3, 5, 9, 1, 7, 8, 1, 9, 0, 3, 9, 9, 5, 5, 5};   

      printElementsOnlyOnce(arr);
    }
}


  
/*
run:
  
[0, 1, 3, 5, 7, 8, 9]
  
*/

 

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