lab/lab1/part4-project-euler.html

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    # Lab 1, Part 4 — Stretch Goal: Project Euler

    ## Introduction

    Practice your Javascript and math skills by solving a problem on Project
    Euler. Project Euler is a series of challenging math and computer science
    problems that can be solved using any language (for our class, use
    Javascript).

    Solve the first problem on this page https://projecteuler.net/archives
    (Multiples of 3 and 5). To check your answer, create an account and you will
    be able to submit your final result.

    If you complete problem 1, move on to problem 2!

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//Problem #1
//If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
//Find the sum of all the multiples of 3 or 5 below 1000.
//Worked with Ian Schwarzenberg
//Code support found via: https://codereview.stackexchange.com/questions/77018/project-euler-1-javascript
var emptyArray = [];//creates an empty array
var answer = 0;//establishes sum variable for use in loop

for (var i = 1; x < 1000; x++) {//establishes look from 1 to 1000
    if (i % 3 === 0 || i % 5 === 0) {//if statement selecting multimpes of 3 OR 5
        emptyArray.push(i);//loop to push variables that are multiple of 3 OR 5
        answer += i;//sums up the variables in the array (answer = answer + i)
    }
}
console.log(answer);//geneates answer of 233168

//Problem #2
//Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:
//1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...
//By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.
//Code support found via: https://stackoverflow.com/questions/39178973/project-euler-2-fibonacci-javascript-attemp

var fibonacci = [0,1];//Establishes 2 variable array with values of 0 and 1
var i = 0;//sets starting point of i to 0
var answer = 0;//establishes sum variable for use in loop
while (fibonacci[0]+fibonacci[1] < 4000000){//establises while loop for values up to 4,000,000
    i= fibonacci[0]+fibonacci[1];//sets loop to add the two previous variables
    fibonacci[0]=fibonacci[1];//establishes variable 0
    fibonacci[1]=i;//establishes variable 1
    if(i%2 === 0){//establishes if statement for remainder set to 0 for i=2*(i/2)
    answer += i;//then returns sums up the variables in the array (answer = answer + i)
    }
}
console.log(answer);//geneates answer of 4613732


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    End code

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