abstracted structures fixed

src/abstract_structures/stacks/stack.py

@@ -1,53 +1,65 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
-__author__ = "Mari Wahl"
-__email__ = "marina.w4hl@gmail.com"
+# copy of the class ../Stack.py
 
-
-''' define the stack class '''
+__author__ = "bt3"
 
 
 class Stack(object):
     def __init__(self):
-        self.items = []
-
-    def isEmpty(self):
-        return not bool(self.items)
+        self.content = []
+        self.min_array = []
+        self.min = float('inf')
 
     def push(self, value):
-        self.items.append(value)
+        if value < self.min:
+            self.min = value
+
+        self.content.append(value)
+        self.min_array.append(self.min)
 
     def pop(self):
-        value = self.items.pop()
-        if value:
+        if self.content:
+            value = self.content.pop()
+            self.min_array.pop()
+            if self.min_array:
+                self.min = self.min_array[-1]
             return value
         else:
-            print("Stack is empty.")
+            return 'Empty List. '
+
+    def find_min(self):
+        if self.min_array:
+            return self.min_array[-1]
+        else:
+            return 'No min value for empty list.'
 
     def size(self):
-        return len(self.items)
+        return len(self.content)
+
+    def isEmpty(self):
+        return not bool(self.content)
 
     def peek(self):
-        if self.items:
-            return self.items[-1]
+        if self.content:
+            return self.content[-1]
         else:
             print('Stack is empty.')
 
+
     def __repr__(self):
-        return '{}'.format(self.items)
-
-
+        return '{}'.format(self.content)
 
 
 if __name__ == '__main__':
-    stack = Stack()
-    print("Is the stack empty? ", stack.isEmpty())
-    print("Adding 0 to 10 in the stack...")
-    for i in range(10):
-        stack.push(i)
-    print("Stack size: ", stack.size())
-    print("Stack peek : ", stack.peek())
-    print("Pop...", stack.pop())
-    print("Stack peek: ", stack.peek())
-    print("Is the stack empty? ", stack.isEmpty())
-    print(stack)
+    q = Stack()
+
+    for i in range(15,20):
+        q.push(i)
+    for i in range(10,5,-1):
+        q.push(i)
+
+
+
+    for i in range(1, 13):
+        print q.pop(), q.find_min()