Problem solving with Functions

Duration: "3:00 - 4:00"
Type: Homework
Class: wdi-cc
Creator: GA Instructional Team
Topics: Problem solving with functions

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Setup

Fork/clone this repo as directed by your instructor. Inside the repo, create the usual folder structure. Write your answers in app.js, following the instructions in today's lab

1. Verbal questions

Write answers to the following questions as comments.

1. What is the difference between a parameter and an argument?
2. Within a function, what is the difference between return and console.log?
3. What are the implications of the ability of a function to return a value?

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🔴 **Commit your work.**
The commit message should read:
"Commit 1 - Verbal questions".

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2. Palindrome again.

Write a function checkPalindrome that accepts a single argument, a string. Yes, you've done it before, but do it again. Later in this assignment we're gonna beef up our palindrome function some. See if you can do it without looking back at your previous answer. The function should return true if the string is a palindrome, false if not. Make sure your function will give the correct answer for words with capital letters.

console.log(checkPalindrome("Radar"));
 => true

console.log(checkPalindrome("Borscht"));
=> false

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🔴 **Commit your work.**
The commit message should read:
"Commit 2 - Palindrome".

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3. Digit Sum

Write a function sumDigits that accepts a number and returns the sum of its digits.

console.log(sumDigits(42));
=> 6;

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🔴 **Commit your work.**
The commit message should read:
"Commit 3 - Digit Sum".

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4. Pythagoras

Write a function calculateSide that takes two arguments: sideA and sideB, and returns the solution for sideC using the Pythagorean theorem.

hint: discover the Pythagorean Theorem on a website called google.com
hint: checkout the Math methods in javascript

console.log(calculateSide(8, 6));
=> 10

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🔴 **Commit your work.**
The commit message should read:
"Commit 4 - Pythagoras".

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5. Sum Array

Write a function sumArray that takes an array as an argument. The array should contain numbers. The function should return the sum of the numbers in the array.

Expected result:

console.log(sumArray([1, 2, 3, 4, 5, 6]));
=> 21

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🔴 **Commit your work.**
The commit message should read:
"Commit 5 - Sum Array".

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6. Prime Numbers

A Prime number is a number that is not evenly divisible by another number except 1 and itself. If you want to read more deeply about it, go here. To test whether a number is Prime, you only need to test as far as the square root of that number. This is advisable for optimization and testing large numbers.

Step One

Write a function called checkPrime that will test whether a number is Prime. The function will return true (Boolean) if Prime, false if not. Hint: Check every number up to the square root. To do this, try a for loop.

Step Two

Write another function called printPrimes that will print (console log) all the Primes up to an arbitrary limit. For example, if you invoke your function with printPrimes(97), it will print all the Prime numbers up to and including 97. This function can call on the previous checkPrime function.

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🔴 **Commit your work.**
The commit message should read:
"Commit 6 - Prime Numbers".

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CSS

Watch the following three videos on CSS:

• First CSS video - 5 minutes
• Second CSS video - 11 minutes
• Third CSS video - 17 minutes

You will need to have watched these videos for tomorrow's lab.

Hungry for more?

1. Complete the afternoon lab.

2. Write a function insertDash that accepts a number as a parameter and returns a string with a dash inserted between any consecutive odd numbers. There should not be a dash at the end, it goes only between numbers.

console.log(insertDash(454793));

=> 4547-9-3

Commit.

3. Write a function reverseString that takes a string as a parameter and returns that string with the letters reversed without using .split(), .reverse(), or .join().

   Commit.

4. Make your palindrome function from problem two above work regardless of spacing (or capitalization). So, for example, "Sit on a potato pan Otis" or "Bird rib" would pass the test.

   Commit.

5. Make your palindrome function work even if the string contains punctuation. So: "Sit on a potato pan, Otis!!!" or "A man, a plan, a canal: Panama." would pass the test.

   Commit.

6. Make a "word palindrome" function that returns true if the words in a phrase are the same backwards and forwards. It should not care about spacing, capitalization, or punctuation. For example the following string would pass the test:

   "Son, I am able," she said. "Though you scare me, watch!" said I, "Beloved," I said, "watch me scare you!" Though, said she: "able am I, son."

   Commit.

7. You still want more?!?! Do you even sleep? Create an account on Project euler and keep working on those problems.