From 0f67559f3c005d1793fb51b3cc30654b15d0f908 Mon Sep 17 00:00:00 2001
From: Austin M Crane <austin.crane@ennovar.wichita.edu>
Date: Wed, 3 Oct 2018 06:56:14 -0500
Subject: [PATCH] Implemented a simple stack algorithm in golang

Created a simple program the uses a integer stack with the following
methods:

Push - adds an item to the stack
Pop - removes top item off the stack
Size - gets the size of the stack
---
 data_structures/stacks/stack.go | 68 +++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 data_structures/stacks/stack.go

diff --git a/data_structures/stacks/stack.go b/data_structures/stacks/stack.go
new file mode 100644
index 0000000..19171c5
--- /dev/null
+++ b/data_structures/stacks/stack.go
@@ -0,0 +1,68 @@
+// Author: Austin Crane
+package main
+
+import (
+	"errors"
+	"fmt"
+)
+
+// Stack is a simple int stack this gives a simple
+// implementation of how stacks are implemented
+type Stack struct {
+	items []int
+}
+
+// Push moves a item onto the top of the stack
+func (s *Stack) Push(n int) {
+	s.items = append(s.items, n)
+}
+
+// Pop gets the top item out of the stack and updates
+// the stack to exclude that "popped" item out of the
+// stack
+func (s *Stack) Pop() (int, error) {
+	if s.Size() == 0 {
+		return 0, errors.New("end of stack reached")
+	}
+
+	var x int
+	x, s.items = s.items[0], s.items[1:]
+	return x, nil
+}
+
+// Size returns count of items in the stack
+func (s *Stack) Size() int {
+	return len(s.items)
+}
+
+// simple helper method to print the popped item
+func popAndPrint(stack *Stack) {
+	n, err := stack.Pop()
+	// there is an error returned if end of stack
+	// is reached
+	if err != nil {
+		fmt.Println(err.Error())
+		return
+	}
+
+	fmt.Printf("Popped: %d\n", n)
+}
+
+func main() {
+	// create an empty stack
+	s := Stack{}
+
+	// add some items to the top of the stack
+	s.Push(1)
+	s.Push(2)
+
+	// print stack size: 2
+	fmt.Printf("Stack size: %d\n", s.Size())
+
+	// pop off 2
+	popAndPrint(&s)
+	// pop off 3
+	popAndPrint(&s)
+	// end of stack is returned
+	popAndPrint(&s)
+}