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Author: Chrischege

Data Structures and Algorithms/stack/README.md

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+# A stack implementation in python
+
+## What is a stack?
+
+A stack is a collection of elements in which the most recent element can be removed
+It uses the LIFO(last in first out) concept. 
+The last item to enter the stack is the first item to leave the stack.
+It can be modelled using a list and the main operations that can be done are POP and PUSH in this case POP and APPEND.
+Stacks are used in real life to build the UNDO and REDO functions where the steps of the user are stored in a stack and the last step can be retraced. like in microsoft word undo and redo function. 

Data Structures and Algorithms/stack/requirements.txt

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+python 3 or a higher version