PHP remove specific item from array

I have an array like : [312, 401, 1599, 3]

With array_diff( [312, 401, 1599, 3], [401] ) I can remove a value, in my example I removed the value 401.

But if I have this : [312, 401, 401, 401, 1599, 3], how can remove just one time the value 401 ?

It is not important if I remove the first or last value, I just need to remove ONE 401 value, and if I want to remove all 401 values, I have to remove three times.

Thanks !

Answer

With array_search you can get the first matching key of the given value, then you can delete it with unset.

if (false !== $key = array_search(401, $array)) {
  unset($array[$key]);
}