How to - Improving my code performance to get unique value from array - Javascript

Question

my code speed performance very slow when to get unique value from array that existing 5000 users data.

There is my code below which has two conditions:

First, to get unique value

Second, to check phone number is null or not, given preference to users data that existing phone number/s.

var arr = [
 ["Wong", ""],
 ["Wong", "0143213123"],
 ["Ali", "0177213123"],
 ["Ali", "0177213123, 0124545345"],
 ["Ali", ""],
 ["Imran", "0133454335"]
];
function uniq(arr) {
 var seen = [];
 for (i = 0; i < arr.length; i++) {
 var a = arr[i][0];
 var a2 = arr[i][1];
 var c = true;
 for (x = 0; x < seen.length; x++) {
 var b = seen[x][0];
 var b2 = seen[x][1];
 if (b == a) {
 c = false;
 if ((b2.trim() == '' || b2.indexOf(',') == -1) && (a2.trim() != '')) {
 seen[x][1] = a2.trim();
 break;
 }
 break;
 }
 }
 if (c == true) {
 seen.push(arr[i]);
 }
 }
 return seen;
}

Result, after code executed:

var arr = uniq(arr);
console.log(arr);
[
 ["Wong", "0143213123"],
 ["Ali", "0177213123, 0124545345"],
 ["Imran", "0133454335"]
];

In jsfiddle here

Answer 1

You could do something like this with reduce and store data in one object for each name.

var arr = [["Wong",""], ["Wong", "0143213123"], ["Ali", "0177213123"], ["Ali", "0177213123, 0124545345"], ["Ali", ""], ["Imran", "0133454335"]];
var uniq = arr.reduce((r, [name, number]) => {
 if(!r[name] || number.trim().length) r[name] = number;
 return r;
}, {});
console.log(Object.entries(uniq))

• Mohamad Izzuddin: Thank @Nenad Vracar , i will test and feedback later (y)