From cc184e61bfc31d5c7b3da1d5a85ac8607d3ae27c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C8=98tefan-Iulian=20Alecu?=
 <165364995+pascalecu@users.noreply.github.com>
Date: Wed, 13 May 2026 22:38:22 +0300
Subject: [PATCH] Add Maximum Subarray in Ruby

---
 archive/r/ruby/maximum-subarray.rb | 36 ++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 archive/r/ruby/maximum-subarray.rb

diff --git a/archive/r/ruby/maximum-subarray.rb b/archive/r/ruby/maximum-subarray.rb
new file mode 100644
index 000000000..f5ebdacff
--- /dev/null
+++ b/archive/r/ruby/maximum-subarray.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+USAGE = 'Usage: Please provide a list of integers in the format: "1, 2, 3, 4, 5"'
+
+def usage!
+  warn USAGE
+  exit 1
+end
+
+def parse_list(str)
+  str.split(",").map { Integer(it.strip) }
+rescue ArgumentError, NoMethodError
+  usage!
+end
+
+def max_subarray_sum(arr)
+  return arr.first if arr.length == 1
+  return arr.sum if arr.none?(&:negative?)
+
+  current = max = arr.first
+
+  arr[1..].each do |x|
+    current = [x, current + x].max
+    max = [max, current].max
+  end
+
+  max
+end
+
+raw = ARGV.first
+usage! if raw.nil? || raw.strip.empty?
+
+arr = parse_list(raw)
+usage! if arr.length < 1
+
+puts max_subarray_sum(arr)