May 6, 2020 · 2 min read

I hope you guys had a great day! I got a lot of work done on my work term report and got a lot of physical activity by going for a jog. Let me know what you guys do to stay active during this pandemic.

For today’s problem, I have to create a function that can basically turn an array of integers and return an array which is incremented by one. That sounded pretty confusing, so I’ll give you guys an example:

`let arr1 = [1, 3, 9];//function returnsarr1 = [1, 4, 0];`

I started out by iterating through the whole array, starting at the end of the array and decrementing the counter for each iteration. If the value at the counter is greater than 9, then I make that digit equal to zero, otherwise, I just return the array after incrementing the digit by one.

`for(let i = digits.length - 1; i >= 0; i--){    digits[i]++;     if(digits[i] > 9)        digits[i] = 0;    else        return digits;    }`

Now if there is a special case, such as when the input array has all entries of 9, then the function would just return an array of zeros, in order to avoid this, I used the .unshift() method in order to add a value at the beginning of the array.

`digits.unshift(1);return digits;`

So the full solution would be:

`var plusOne = function(digits) {    for(var i = digits.length - 1; i >= 0; i--){     digits[i]++;     if(digits[i] > 9)        digits[i] = 0;    else        return digits;    }    digits.unshift(1);    return digits;};`

Let me know if you guys have any questions or any comments below! Thanks.

## The Startup

Get smarter at building your thing. Join The Startup’s +793K followers.

### By The Startup

Get smarter at building your thing. Subscribe to receive The Startup's top 10 most read stories — delivered straight into your inbox, once a week. Take a look.

Medium sent you an email at to complete your subscription.

Written by

## The Startup

Get smarter at building your thing. Follow to join The Startup’s +8 million monthly readers & +793K followers.

Written by

## The Startup

Get smarter at building your thing. Follow to join The Startup’s +8 million monthly readers & +793K followers.