Perl implements high waterline algorithm (solution method for multi-value comparison problem)

"High Waterline" algorithm: After the flood, when the last wave fades, the high waterline will indicate the highest water level seen.
Let’s take a look at the application of the “high waterline” algorithm in Perl.

#! /usr/bin/perl; 
use utf8; 
 
sub max { 
  my($max_so_far) = shift @_; #The first value in the array is temporarily regarded as the maximum value.  foreach(@_){         #Transfer the array @_  if($_>$max_so_far){     #See if other elements have a larger value than $max_so_far.  $max_so_far = $_;}     #If there is any, update the maximum value variable  } 
  $max_so_far; 
} 
 
my $_MaxData = &max(2,3,8,5,10); 
print $_MaxData; 

The first line performs shift operation on the array @_, puts an element 2 into the maximum value $max_so_far variable, the remaining elements in @_ are (3,8,5,10), and then loops through the array with foreach. The first element in the new array is 3 to 2, and is moved to the $max_so_far variable, and so on. The last 10 is the largest element in the array.