feat: add ruby code - chapter stack and queue (#1230)

codes/ruby/chapter_stack_and_queue/stack.rb

@@ -0,0 +1,36 @@
+=begin
+File: stack.rb
+Created Time: 2024-04-06
+Author: Xuan Khoa Tu Nguyen (ngxktuzkai2000@gmail.com)
+=end
+
+### Driver Code ###
+
+# 初始化栈
+# Ruby 没有内置的栈类，可以把 Array 当作栈来使用
+stack = []
+
+# 元素入栈
+stack << 1
+stack << 3
+stack << 2
+stack << 5
+stack << 4
+puts "栈 stack = #{stack}"
+
+# 访问栈顶元素
+peek = stack.last
+puts "栈顶元素 peek = #{peek}"
+
+# 元素出栈
+pop = stack.pop
+puts "出栈元素 pop = #{pop}"
+puts "出栈后 stack = #{stack}"
+
+# 获取栈的长度
+size = stack.length
+puts "栈的长度 size = #{size}"
+
+# 判断是否为空
+is_empty = stack.empty?
+puts "栈是否为空 = #{is_empty}"