Your PHP script should take an array of integers as input and output the length of the longest increasing subsequence in the array.
user
Assume an unsorted array of integers as input. First, iterate through the array and keep track of the length of the increasing subsequence that ends at each number. This subsequence can be found by comparing the previous numbers in the array to the current number. The longest increasing subsequence can then be found by selecting the maximum length of any of the subsequences found. 

# Function to find length of longest increasing subsequence in an unsorted array

function longest_subsequence($array) {

   # Initialize a list to store increasing subsequence lengths

   $sub_list = [];

   # Iterate through the array and find the length of increasing subsequence ending at each number

   for($i = 0; $i < $count; $i++) {

      # Keep track of previous number in the array

      $prev = -1;

      $length = 1;

      # Check if the current number is greater than the previous number

      if($i > 0) {

         // The current number is greater than or equal to the previous number

         if($array[$i] >= $array[$i - 1]) {

         // The current number is less than the previous number

         } else {

         // The current number is greater than the previous number

         if($prev!= $array[$i - 1]) {

         $length++;

         }

      }

      }

      # Add the length of the increasing subsequence ending at the current number to the list

      $sub_list[] = $length;

   }

   # Find the maximum length of increasing subsequence in the list

   $max_length = max($sub_list);

   # Return the maximum length of increasing subsequence

   return $max_length;

}

# Input: array of integers

$array = array(10, 9, 2, 5, 3, 7, 101, 18);

# Output: length of longest increasing subsequence in the array (6)

echo longest_subsequence($array);
assistant
Your PHP script should take an array of integers as input and output the length of the longest increasing subsequence in the array.
user
I can provide you with a code snippet to solve this problem:

```
function lengthoflis($nums) {
    $dp = array(); // create a dynamic programming array
    $max = 1;
    for ($i = 0; $i < count($nums); $i++) {
        $dp[$i] = 1;
        for ($j = 0; $j < $i; $j++) {
            if ($nums[$j] < $nums[$i]) {
                $dp[$i] = max($dp[$i], $dp[$j] + 1);
            }
        }
        $max = max($max, $dp[$i]);
    }
    return $max;
}
```

the `lengthoflis` function takes an array of integers as input and uses dynamic programming to find the length of the longest increasing subsequence. We create a dynamic programming array and iterate over the input array, keeping track of the length of the longest increasing subsequence that ends at each position in the input array. We use a nested loop to compare the current element to all previous elements and update the length of the longest increasing subsequence ending at the current element if we find a smaller element that it can be appended to. We then update the maximum length seen so far and return that value. 

to use this function, simply call `lengthoflis` with an array of integers as the argument:

```
$nums = array(10, 9, 2, 5, 3, 7, 101, 18);
echo lengthoflis($nums); // output: 4
``` 

this will output the length of the longest increasing subsequence in the input array, which is 4 in this case.
assistant