How to find closest value in multidimensional array?

Question

PHP

Hello.
I don’t know how exactly to formulate the question correctly, I write it as it is:
Given a multidimensional array of the following form:

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

An array always consists of arrays of 3 elements and is sorted in ascending order. And given for example the following array: How to find the value in the first array that would be closest (less than or equal) to the second array. For example, for this case it will be the value [1, 5, 4]. I hope the point is clear.
[1, 5, 5]

Answer 1

Once sorted, then you just need to go in a row until there is an element that exceeds the given values. Return previous.

function nearest( $sample, $arr) {
  $found = false;
  foreach( $arr AS $row) {
    if($row[0] <= $sample[0]  &&  $row[1] <= $sample[1]  &&  $row[2] <= $sample[2]) $found = $row;
    else break;
  }
  
  return $found;
}

$data = [
  [1, 1, 1],
  [1, 2, 1],
  [1, 2, 2],
  [1, 5, 4],
  [1, 5, 6],
  [2, 1, 6],
  [2, 2, 2],
];

echo implode(',', nearest( [1,5,5], $data)); //  1,5,4