unique_array.js

// Using Set
function uniqArray(a) {
    return [...new Set(a)];
}
console.log(uniqArray([]))
console.log(uniqArray([1, 2, 3, 4]))
console.log(uniqArray([1, 2, 1, 3, 2, 4]));
console.log(uniqArray([1, 1, 1]));


// Interating over array using Memo
function uniqArray(a) {
    var seen = {};
    return a.filter((item) => {
        return seen.hasOwnProperty(item) ? false : (seen[item] = true);
    });
}
console.log(uniqArray([]))
console.log(uniqArray([1, 2, 3, 4]))
console.log(uniqArray([1, 2, 1, 3, 2, 4]));
console.log(uniqArray([1, 1, 1]));