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# Algorithm Solutions

Takes 5 minutes

I’ve completed three more Free Code Camp algorithms since my last go on May 30th.

I needed less guidance on these particular algorithms, all but one. The algorithm solutions weren’t too hard to come up with, however on Slasher FLick I really overcomplicated my solution. I was thinking way too hard about how to solve it— new array? Should I `return newArray` as a part of the function call? Do I `push` the result of the cut off part of the array into `newArray`?

The instructions were:

Return the remaining elements of an array after chopping off n elements from the head. The head means the beginning of the array, or the zeroth index. Remember to use Read-Search-Ask if you get stuck. Write your own code. Here are some helpful links: Array.slice() Array.splice()

Seems simple enough. But I was thinking too much and making it more complex than it needed to be because of my recent previous solutions.

I used `splice` instead of `slice` as `splice` returns the chopped off part as a new array. For these instructions, here was the initial code:

[javascript]

function slasher(arr, howMany) {

// it doesn’t always pay to be first

}

slasher([“burgers”, “fries”, “shake”], 1);

[/javascript]

Originally I had this:

function slasher(arr, howMany) { // it doesn't always pay to be first var newArray = []; arr.splice(0, howMany); return newArray; } slasher(["burgers", "fries", "shake"], 1);

I would get a double array, because like I said, `splice` returns a new array from the chopped off part. So I tried to use a non-initialized variable— `var newArray;`— that returned a TypeError.

I went to the Free Code Camp wiki to look at the explanation in more detail. I finally came up with an Aha! Moment. I only needed to return the array that was resulting in the `splice` method.

I settled on my final solution here:

function slasher(arr, howMany) { // it doesn't always pay to be first arr.splice(0, howMany); return arr; } slasher(["burgers", "fries", "shake"], 1);

## Getting Easier?

That one was easier to do. I hardly needed any help from Gitter. But then…

Mutations.

The instructions:

Mutations

I thought, okay. I got this.

The code:

function mutation(arr) { } mutation(["hello", "hey"]);

I started out with this:

function mutation(arr) { for (var i = 0; i < arr.length; i++) { if (arr === arr.indexOf(i)) { return true; } else { return false; } } mutation(["hello", "hey"]);

That didn’t work. I went to Gitter.

A guy there told me I needed to compare two arrays. I couldn’t figure out what he meant by that. To the wiki.

There I found out I should use `toLowerCase` and think about turning the array strings into an array of `chars`.

So then I came up with this:

var arr1 = arr.toLowerCase(); var arr2 = arr.toLowerCase(); var chars = arr1.split(" ");

as part of the equation. That also didn’t work. By this time, I am tired, it is late and I just wanted this to work. I went back to the wiki and found the solution.

I wouldn’t have ever came up with this yesterday night:

function mutation(arr) { var arr1 = arr[1].toLowerCase(); var arr2 = arr[0].toLowerCase(); for (var i = 0; i < arr1.length; i++) { if (arr2.indexOf(arr1[i]) < 0) return false; } return true; } mutation(["hello", "hey"]);

I am studying this. I am trying to figure out what is going on here and I will probably go to Code Newbie Slack to ask around.

## Back At It

I am doing the Falsy Bouncer algorithm after this post. It looks easy enough, and if I get stuck I will go to Gitter instead of the wiki as the solutions are there. You don’t have to look, but I was tired and frustrated last night which is never a good mix.

I’ve completed three more Free Code Camp algorithms since my last go on May 30th.

I needed less guidance on these particular algorithms, all but one. The algorithm solutions weren’t too hard to come up with, however on Slasher FLick I really overcomplicated my solution. I was thinking way too hard about how to solve it— new array? Should I `return newArray` as a part of the function call? Do I `push` the result of the cut off part of the array into `newArray`?

The instructions were:

Return the remaining elements of an array after chopping off n elements from the head. The head means the beginning of the array, or the zeroth index. Remember to use Read-Search-Ask if you get stuck. Write your own code. Here are some helpful links: Array.slice() Array.splice()

Seems simple enough. But I was thinking too much and making it more complex than it needed to be because of my recent previous solutions.

I used `splice` instead of `slice` as `splice` returns the chopped off part as a new array. For these instructions, here was the initial code:

[javascript]

function slasher(arr, howMany) {

// it doesn’t always pay to be first

}

slasher([“burgers”, “fries”, “shake”], 1);

[/javascript]

Originally I had this:

function slasher(arr, howMany) { // it doesn't always pay to be first var newArray = []; arr.splice(0, howMany); return newArray; } slasher(["burgers", "fries", "shake"], 1);

I would get a double array, because like I said, `splice` returns a new array from the chopped off part. So I tried to use a non-initialized variable— `var newArray;`— that returned a TypeError.

I went to the Free Code Camp wiki to look at the explanation in more detail. I finally came up with an Aha! Moment. I only needed to return the array that was resulting in the `splice` method.

I settled on my final solution here:

function slasher(arr, howMany) { // it doesn't always pay to be first arr.splice(0, howMany); return arr; } slasher(["burgers", "fries", "shake"], 1);

## Getting Easier?

That one was easier to do. I hardly needed any help from Gitter. But then…

Mutations.

The instructions:

Mutations

I thought, okay. I got this.

The code:

function mutation(arr) { } mutation(["hello", "hey"]);

I started out with this:

function mutation(arr) { for (var i = 0; i < arr.length; i++) { if (arr === arr.indexOf(i)) { return true; } else { return false; } } mutation(["hello", "hey"]);

That didn’t work. I went to Gitter.

A guy there told me I needed to compare two arrays. I couldn’t figure out what he meant by that. To the wiki.

There I found out I should use `toLowerCase` and think about turning the array strings into an array of `chars`.

So then I came up with this:

var arr1 = arr.toLowerCase(); var arr2 = arr.toLowerCase(); var chars = arr1.split(" ");

as part of the equation. That also didn’t work. By this time, I am tired, it is late and I just wanted this to work. I went back to the wiki and found the solution.

I wouldn’t have ever came up with this yesterday night:

function mutation(arr) { var arr1 = arr[1].toLowerCase(); var arr2 = arr[0].toLowerCase(); for (var i = 0; i < arr1.length; i++) { if (arr2.indexOf(arr1[i]) < 0) return false; } return true; } mutation(["hello", "hey"]);

I am studying this. I am trying to figure out what is going on here and I will probably go to Code Newbie Slack to ask around.

## Back At It

I am doing the Falsy Bouncer algorithm after this post. It looks easy enough, and if I get stuck I will go to Gitter instead of the wiki as the solutions are there. You don’t have to look, but I was tired and frustrated last night which is never a good mix.

I will also be reading all the algorithm books I have and the Coursera courses I downloaded from Stanford.