Array Duplicate removal

by Krishna Ananthi

JavaScript

let a = [1, 2, 5, 2, 1, 8];
 console.log('Method 1',Array.from(new Set(a))); 
 console.log('Method 2',[...new Set(a)]);

     let b = [];
     let len = a.length;
     for (let i = 0; i < len; i++) {
       if (!b.includes(a[i])) {
         b.push(a[i]);
       }
     }
     console.log('Method 3',b);


     b = []; len = a.length;
     for (let i = 0; i < len; i++) {
       if (b.indexOf(a[i]) === -1) {
         b.push(a[i]);
       }
     }
     console.log('Method 4',b);

     let obj = {}
     for (let i of a) {
       obj[i] = true;
     }

     console.log('Method 5',Array.from(Object.keys(obj).map(Number)));
     console.log('Method 6',[...Object.keys(obj).map(Number)]);