Sunset Hills Challenge

Background

The Sunset Hills coding challenge is intended to assess a candidate’s ability to work with Arrays. This challenge or a slight variation has been used by technology companies such as Amazon and was also featured on a Geeks for Geeks blog post titled “Amazon Interview Experience | Set 189 (For SDE-1)”

Description

An array of buildings is facing the sun. The heights of each building from West to East is given in an integer array. You have to tell which buildings will be able to see the sunset. Write a program that prints how many buildings and which buildings will be able to see the Sunset given the Array [3, 2, 4, 7, 6, 9]. The output should look something like this:4 --> [3, 4, 7, 9]

Allow the user to enter their own values into an array before determining who can see the Sunset.

Solve

Code

The following is my Java-script code used for this exercise. Read over if your interested.


//Event Listener for JS
document.getElementById("btnSunset").addEventListener("click", sunHills);

function sunHills() {
    //Step 1: Add event listener for button click
    //On my main index Page towards the bottom

    //Step 2: Gather user input the put into an array
    let bldgHeight1 = Number(document.getElementById("txtSunsetIn1").value);
    let bldgHeight2 = Number(document.getElementById("txtSunsetIn2").value);
    let bldgHeight3 = Number(document.getElementById("txtSunsetIn3").value);
    let bldgHeight4 = Number(document.getElementById("txtSunsetIn4").value);
    let bldgHeight5 = Number(document.getElementById("txtSunsetIn5").value);

    var bldgArray = []; //initial Array
    var result = [];  //Result array
    bldgArray.push(bldgHeight1);
    bldgArray.push(bldgHeight2);
    bldgArray.push(bldgHeight3);
    bldgArray.push(bldgHeight4);
    bldgArray.push(bldgHeight5);

    //Step 3: Traverse array from right to left. And keep track of bldgs the can see sunset
    // Length of the array; array is > 0; decrements by 1
    // checking current index to see if it's greater than the next
    // Lastly pushes to the bldg array
    for (let i = bldgArray.length - 1; i > 0; i--) {
        if (bldgArray[i] > bldgArray[i - 1]) {
            result.push(bldgArray[i])
        }
    };

    // since 0 will always see sun it will be pushed
    // reverse array to appropriate
    result.push(bldgArray[0])
    result.reverse()

    //Step 4: Out to the user on which buildings can sunset
    //Where result will go
    document.getElementById("SSoutput").innerHTML = "Count: " + `${result.length}` + ", [" + `${result}` + "]"
};

Technologies

Technologies Used: HTML, CSS, JavaScript, jQuery and Bootstrap. Made in VS Studio 2019 with code on GitHub.