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Bonfire Return Largest Numbers in Arrays

Rafael J. Rodriguez edited this page Jan 6, 2017 · 2 revisions



Created by Rafase282

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  • Difficulty: 1/5

Return an array consisting of the largest number from each provided sub-array. For simplicity, the provided array will contain exactly 4 sub-arrays.

Remember, you can iterate through an array with a simple for loop, and access each member with array syntax arr[i] .

If you are writing your own Chai.js tests, be sure to use a deep equal statement instead of an equal statement when comparing arrays.

Remember to use Read-Search-Ask if you get stuck. Try to pair program. Write your own code.

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Problem Script:

function largestOfFour(arr) {
  // You can do this!
  return arr;

largestOfFour([[4, 5, 1, 3], [13, 27, 18, 26], [32, 35, 37, 39], [1000, 1001, 857, 1]]);


You will get an array that contains sub arrays of numbers and you need to return an array with the largest number from each of the sub arrays.

Hint: 1

You will need to keep track of the array with the answer and the largest number of each sub-array.

Hint: 2

You can work with multidimensional arrays by Array[Index][SubIndex]

Hint: 3

Pay close attention to the timing of the storing of variables when working with loops

My code:

function largestOfFour(arr) {
  var results = [];
  for (var n in arr) {
      var largestNumber = 0;
      for (var sb in arr[n]) {
          if (arr[n][sb] > largestNumber) {
              largestNumber = arr[n][sb];
    results[n] = largestNumber;
  return results;

My Code Explanation:

  • Create a variable to store the results as an array.
  • Create an outer loop to iterate through the main array.
  • Before going into the inner loop, create a variable to hold the largest number. This must be outside the inner loop.
  • Create another for loop to work with the sub-arrays.
  • Check if the element of the sub array is larger than the current largest number. If so, then save the number.
  • After the inner loop, save the largest number in the variable for the results.

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