Good afternoon! Here's our prompt for today.

We're given an array of continuous numbers that should increment sequentially by 1, which just means that we expect a sequence like:

[1, 2, 3, 4, 5, 6, 7]

However, we notice that there are some missing numbers in the sequence.

[1, 2, 4, 5, 7]

Can you write a method missingNumbers that takes an array of continuous numbers and returns the missing integers?

1missingNumbers([1, 2, 4, 5, 7]);
2// [3, 6]

Constraints

• Length of the array <= 100000
• The array will always contain non negative integers (including 0)
• Expected time complexity : O(n)
• Expected space complexity : O(1)

Try to solve this here or in Interactive Mode.

How do I practice this challenge?

xxxxxxxxxx

    'PASSED: missingNumbers([3, 7, 9, 19]) should equal [ 4, 5, 6, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18 ]'

var assert = require('assert');

​

function missingNumbers(numArr) {

  let missing = [];

  return missing;

}

​

try {

  assert.deepEqual(missingNumbers([0, 1, 3]), [2]);

​

  console.log('PASSED: ' + 'missingNumbers([0, 1, 3]) should equal [2]');

} catch (err) {

  console.log(err);

}

​

try {

  assert.deepEqual(missingNumbers([10, 11, 14, 17]), [12, 13, 15, 16]);

​

  console.log(

    'PASSED: missingNumbers([10, 11, 14, 17]) should equal [ 12, 13, 15, 16 ]'

  );

} catch (err) {

  console.log(err);

}

​

try {

  assert.deepEqual(

    missingNumbers([3, 7, 9, 19]),

    [4, 5, 6, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18]

Here's a video of us explaining the solution.

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Here's our guided, illustrated walk-through.

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