now is go gettable and updated make file

cmd/micro/stack.go

@@ -0,0 +1,43 @@
+package main
+
+// Stack is a simple implementation of a LIFO stack
+type Stack struct {
+	top  *Element
+	size int
+}
+
+// An Element which is stored in the Stack
+type Element struct {
+	value interface{} // All types satisfy the empty interface, so we can store anything here.
+	next  *Element
+}
+
+// Len returns the stack's length
+func (s *Stack) Len() int {
+	return s.size
+}
+
+// Push a new element onto the stack
+func (s *Stack) Push(value interface{}) {
+	s.top = &Element{value, s.top}
+	s.size++
+}
+
+// Pop removes the top element from the stack and returns its value
+// If the stack is empty, return nil
+func (s *Stack) Pop() (value interface{}) {
+	if s.size > 0 {
+		value, s.top = s.top.value, s.top.next
+		s.size--
+		return
+	}
+	return nil
+}
+
+// Peek returns the top element of the stack without removing it
+func (s *Stack) Peek() interface{} {
+	if s.size > 0 {
+		return s.top.value
+	}
+	return nil
+}