Could you write me a ruby program which reads a csv file (server log) with two columns. First column is IP address and second how many times this IP address send request to your server. I want to get as out put of the program the top 5 IP addresses with the most requests ordered desc.
user
Sure! Here's a simple Ruby program that does exactly that:

```ruby
require 'csv'

def top_five_ips(file_path)
  ip_counts = Hash.new(0)

  CSV.foreach(file_path, headers: false) do |row|
    ip = row[0]
    count = row[1].to_i
    ip_counts[ip] += count
  end

  sorted_ips = ip_counts.sort_by { |_ip, count| -count }

  top_five = sorted_ips[0...5]

  top_five.each do |ip, count|
    puts "#{ip}: #{count} requests"
  end
end

file_path = 'server_log.csv'
top_five_ips(file_path)
```

The program uses the `CSV` library to read the log file and parse each line into an IP address and a request count. It stores these counts in a hash, where the IP address is the key and the count is the value.

Once all of the IP addresses have been processed, the program sorts the hash by count in descending order and takes the first five elements to get the top 5 IP addresses.

Finally, it prints out the IP addresses and their request count in the desired format.

Note that this program assumes that the input file is properly formatted, with each line containing two values: an IP address and a count.
assistant
It is critical to me that the program has as little requirements as possible.
Could you modify it to parse the CSV without the use of a library?
user
Sure, here's a modified version of the program that parses the CSV file without using a library:

def top_five_ips(file_path)
  ip_counts = Hash.new(0)

  File.open(file_path, 'r').each_line do |line|
    fields = line.strip.split(',')
    ip = fields[0]
    count = fields[1].to_i
    ip_counts[ip] += count
  end

  sorted_ips = ip_counts.sort_by { |_ip, count| -count }

  top_five = sorted_ips[0...5]

  top_five.each do |ip, count|
    puts "#{ip}: #{count} requests"
  end
end

file_path = 'server_log.csv'
top_five_ips(file_path)


This version of the program uses the File class to open the input file and iterate over each line, splitting each line on commas to extract the IP address and request count. The rest of the logic is the same as before.

This program has fewer requirements than the original version, as it doesn't require the csv library. However, it may be less flexible and may not handle edge cases as well as the csv library.
assistant