how to return unique items of an array in javascript code example

Example 1: javascript array unique values

var arr = [55, 44, 65,1,2,3,3,34,5];
var unique = [...new Set(arr)]

//just  var unique = new Set(arr) wont be an array

Example 2: find unique elements in array javascript

let a = ["1", "1", "2", "3", "3", "1"];
let unique = a.filter((item, i, ar) => ar.indexOf(item) === i);
console.log(unique);

Example 3: unique elements in array javascript

var array3 = [1, 2, 4, 6, 1, 4, 9, 10, 2, 8];
function findUniqueElements_3(array) {

    for (let i = 0; i < array.length; i++) {
        for (let j = i + 1; j < array.length; j++) {
            if (array[i] == array[j]) {
                array.splice(j, 1)
            }

        }
    }
    console.log(`from third way : ${array}`);
}

findUniqueElements_3(array3)

Example 4: unique numbers in array

import java.util.ArrayList;

public class UniqueNumbersInArray {

    public static void main(String[] args) {


    int arr[] = { 4,5,5,4,5,6,5,8,4,7};

        ArrayList<Integer> uniqueArr = new ArrayList<Integer>();
        for (int i = 0; i < arr.length; i++) {

            int k = 0;
            if (!uniqueArr.contains(arr[i])){
                uniqueArr.add(arr[i]);
                k++;

                for (int j = i; j < args.length ; j++) {
                    if (arr[i]==arr[j]){
                        k++;
                    }
                }

                System.out.println(arr[i]);
                System.out.println(k);
            }

        }
    }
}

Tags:

Java Example