Уникальное значение массива

let arr = [1,2,4,5,3,5,2,1,3]; 
let uniqArr = arr.filter((val, i, ar) => ar.indexOf(val) === i); 
console.log(uniqArr);

   var arr1 = [1,2,4,5,3,5,2,1,3]; 
    let set = new Set(arr1); 
    let res = Array.from(set); 
    console.log(res);

function unique(arr) { 
  var obj = {}; 
 
  for (var i = 0; i < arr.length; i++) { 
    var str = arr[i]; 
    obj[str] = true; 
  } 
 
  return Object.keys(obj); 
} 
 
var arr1 = [1,2,4,5,3,5,2,1,3]; 
 
console.log(unique(arr1));

var arr1 = [1,2,4,5,3,5,2,1,3]; 
console.log(_.uniq(arr1));

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