freeCodeCamp/curriculum/challenges/english/blocks/daily-coding-challenges-javascript/69f35a5bb823ed620fcb7cbe.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
69f35a5bb823ed620fcb7cbe	Challenge 285: Meeting Time	28	challenge-285

--description--

Given a 3D array representing availability windows for multiple people, return the earliest time where everyone has one hour free. If no such time exists, return "None".

• Each person's availability is an array of [start, end] integer pairs in 24-hour time. For example, [10, 12] would mean the person is available from 10 to 12. Start times range from 0-23, and end times range from 1-24.

For example, given:

[
  [[10, 12], [15, 16]], // person 1
  [[11, 14], [15, 16]]  // person 2
]

Return 11, the start of their first shared free hour.

--hints--

getMeetingTime([[[10, 12], [15, 16]], [[11, 14], [15, 16]]]) should return 11.

assert.equal(getMeetingTime([[[10, 12], [15, 16]], [[11, 14], [15, 16]]]), 11);

getMeetingTime([[[9, 10], [12, 15]], [[10, 11], [13, 14]], [[9, 11], [10, 14]]]) should return 13.

assert.equal(getMeetingTime([[[9, 10], [12, 15]], [[10, 11], [13, 14]], [[9, 11], [10, 14]]]), 13);

getMeetingTime([[[7, 8], [9, 11], [12, 14], [15, 16]], [[8, 11], [12, 13], [14, 15]]]) should return 9.

assert.equal(getMeetingTime([[[7, 8], [9, 11], [12, 14], [15, 16]], [[8, 11], [12, 13], [14, 15]]]), 9);

getMeetingTime([[[7, 8], [10, 12], [13, 15]], [[8, 11], [12, 13], [14, 15]], [[6, 7], [8, 9], [12, 13]]]) should return None.

assert.equal(getMeetingTime([[[7, 8], [10, 12], [13, 15]], [[8, 11], [12, 13], [14, 15]], [[6, 7], [8, 9], [12, 13]]]), "None");

getMeetingTime([[[1, 3], [4, 6], [8, 10], [20, 23]], [[15, 16], [17, 18], [19, 22], [23, 24]], [[14, 16], [17, 23]], [[2, 4], [5, 6], [18, 19], [21, 22], [23, 24]]]) should return 21.

assert.equal(getMeetingTime([[[1, 3], [4, 6], [8, 10], [20, 23]], [[15, 16], [17, 18], [19, 22], [23, 24]], [[14, 16], [17, 23]], [[2, 4], [5, 6], [18, 19], [21, 22], [23, 24]]]), 21);

--seed--

--seed-contents--

function getMeetingTime(availability) {

  return availability;
}

--solutions--

function getMeetingTime(availability) {
  for (let hour = 0; hour < 24; hour++) {
    const allFree = availability.every(person =>
      person.some(([start, end]) => start <= hour && hour + 1 <= end)
    );
    if (allFree) return hour;
  }
  return "None";
}