Birthday Cake Candles

 

 

Problem

You are in charge of the cake for your niece's birthday and have decided the cake will have one candle for each year of her total age. When she blows out the candles, she’ll only be able to blow out the tallest ones. Your task is to find out how many candles she can successfully blow out.

For example, if your niece is turning  4years old, and the cake will have  4candles of height 4,4,1,3 she will be able to blow out 2 candles successfully since the tallest candles are of height 4 and there are 2 such candles.

 

 

 

 

 

Solution in JavaScript

const arr = [2, 7, 4, 6, 7];

function birthdayCakeCandles(arr) {
    //Math.max returns maximum value in the array.
    const max = Math.max(...arr);

    //filter() methods creates a new array with all elements 
    //that pass the test implemented by the provided function
    const filtered = arr.filter( elem => elem === max);

    const result = filtered.length;

    console.log(result); //2
}

birthdayCakeCandles(arr);

 

 

 

 

 

Reference

https://www.hackerrank.com/challenges/birthday-cake-candles/problem

Birthday Cake Candles | HackerRank

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter

Array.prototype.filter()

https://www.w3schools.com/js/js_math.asp

JavaScript Math Object