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# Find smallest positive integer from array in Javascript

- Authors
- Name
- Dhaval Vyas
- @VyasDhaval_

This article is about finding the smallest positive integer from an array.

## Option 1

```
const arr = [1,4,53,9,10,43];
const sorted = arr.sort((a,b) => (a-b));
retrun sorted[0]; // 1
```

Option 1 looks clean but the time complexity of the above solution is O(n log(n)). There is a better way to achieve this. Check out option 2.

## Option 2

```
const arr = [1, 4, 53, 9, 10, 43]
function findSmallest(_arr) {
let smallest = _arr[0]
for (let i = 0; i < _arr.length; i++) {
if (_arr[i] < smallest) {
smallest = _arr[i]
}
}
return smallest
}
findSmallest(arr) // 1
```

Performance of Option 2 is better than Option 1. You can create this as a utility function in your project. Checkout this benchmark here.

## Option 3

There is another option that we can use to find the smallest number. Nifty little trick. Credit goes to Louis St-Amour who reached out on LinkedIn with this option.

```
const arr = [1,4,53,9,10,43];
const sorted = arr.reduce((smallest, c) => c < smallest ? c : smallest);
retrun sorted; // 1
```

This uses Array.reduce method to reduce to the smallest number. Callback inside reduce method is called for each element in the array and keep track of the smallest number.