let old_arr = [3, 3, '4', '444', 1, '444', 'fdsf', 1, 'fsdf', '90909'],
new_arr = []; // 3 '4' '444'
old_arr.forEach(function(value) {
let isSave = 34;
for (let i = 0; i < new_arr.length; i++) {
if (value == new_arr[i]) {
isSave = 35;
}
}
if (isSave == 34) {
new_arr.push(value);
}
})
console.log(new_arr);