Radix Sort Algorithm in DSA Javascript - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the digit at a specific place value.

DSA Javascript

function getDigit(num, place) {
  return Math.floor(Math.abs(num) / [1]) % 10;
}

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A10 ** place

Bplace * 10

Cplace + 10

D10 * place

Attempts:

3 left

💡 Hint

Common Mistakes

Using multiplication instead of exponentiation for place value.

Not using Math.floor to remove decimals.

The digit at a given place is found by dividing the number by 10 raised to that place, then taking the remainder when divided by 10.

2fill in blank

medium

Complete the code to count the number of digits in a number.

DSA Javascript

function digitCount(num) {
  if (num === 0) return 1;
  return Math.floor(Math.log10(Math.abs(num))) + [1];
}

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A0

B1

C10

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to add 1 after log10.

Not handling zero correctly.

Adding 1 after floor of log base 10 gives the total digits count.

3fill in blank

hard

Fix the error in the code to find the maximum number of digits in an array.

DSA Javascript

function mostDigits(nums) {
  let maxDigits = 0;
  for (let i = 0; i < nums.length; i++) {
    maxDigits = Math.max(maxDigits, [1](nums[i]));
  }
  return maxDigits;
}

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AMath.abs

BgetDigit

CMath.log10

DdigitCount

Attempts:

3 left

💡 Hint

Common Mistakes

Using getDigit which returns a single digit, not count.

Using Math.log10 directly without floor or handling zero.

We use digitCount to find how many digits each number has and track the maximum.

4fill in blank

hard

Fill both blanks to correctly place numbers into buckets by digit and flatten the array.

DSA Javascript

for (let k = 0; k < maxDigitCount; k++) {
  let buckets = Array.from({ length: 10 }, () => []);
  for (let i = 0; i < nums.length; i++) {
    let digit = [1](nums[i], k);
    buckets[digit].[2](nums[i]);
  }
  nums = [].concat(...buckets);
}

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AgetDigit

Bpush

Cpop

Dshift

Attempts:

3 left

💡 Hint

Common Mistakes

Using pop or shift which remove elements instead of adding.

Using digitCount instead of getDigit here.

getDigit gets the digit at place k; push adds the number to the correct bucket.

5fill in blank

hard

Fill all three blanks to complete the radix sort function.

DSA Javascript

function radixSort(nums) {
  let maxDigitCount = [1](nums);
  for (let k = 0; k < maxDigitCount; k++) {
    let buckets = Array.from({ length: 10 }, () => []);
    for (let i = 0; i < nums.length; i++) {
      let digit = [2](nums[i], k);
      buckets[digit].push(nums[i]);
    }
    nums = [].concat(...buckets);
  }
  return nums;
}

// Helper functions
function digitCount(num) {
  if (num === 0) return 1;
  return Math.floor(Math.log10(Math.abs(num))) + 1;
}

function mostDigits(nums) {
  let maxDigits = 0;
  for (let i = 0; i < nums.length; i++) {
    maxDigits = Math.max(maxDigits, digitCount(nums[i]));
  }
  return maxDigits;
}

function getDigit(num, place) {
  return Math.floor(Math.abs(num) / (10 ** place)) % 10;
}

Drag options to blanks, or click blank then click option'

AmostDigits

BgetDigit

CdigitCount

DMath.max

Attempts:

3 left

💡 Hint

Common Mistakes

Using digitCount instead of mostDigits for maxDigitCount.

Using digitCount inside the loop instead of getDigit.

mostDigits finds max digits in array, getDigit gets digit at place, digitCount counts digits.