Find top 3 and bottom 2 values from the list in O(n)

README.md

@@ -52,7 +52,8 @@ Collection of interesting questions and solutions that involve data structures,
 9. [Write an "echo" program](https://github.com/harishvc/challenges/blob/master/cmd-line-echo.py) 
 10. [Given a list of size n, find the majority element](https://github.com/harishvc/challenges/blob/master/majority-value.py)
 11. [Find min value of two unsorted lists](https://github.com/harishvc/challenges/blob/master/min-value-two-unsorted-lists.py) :bulb: :thumbsup:
-12. [Given a string where each character can be [0-9] or [+-*] find the result](https://github.com/harishvc/challenges/blob/master/stack-calculator.py) :thumbsup: 
+12. [Given a string where each character can be [0-9] or [+-*] find the result](https://github.com/harishvc/challenges/blob/master/stack-calculator.py) :thumbsup:
+13. [Find top 3 and bottom 2 values from the list in O(n)](https://github.com/harishvc/challenges/blob/master/find-top-3-bottom-3-values-in-a-list.py) :thumbsup:  
 
 ### Brain Teasers (Moderate)
 1. [Check if a given number is prime](https://github.com/harishvc/challenges/blob/master/prime.py)

find-top-3-bottom-3-values-in-a-list.py

@@ -0,0 +1,67 @@
+'''
+Question: Find top 3 and bottom 2 values from the list in O(n)
+'''
+
+
+input = [20,5,6,100,3]
+
+t1,t2,t3,it1,it2,it3,b1,b2,ib1,ib2 = None,None,None,None,None,None,None,None,None,None
+for i,x in enumerate(input):
+    ############
+    #BOTTOM 1,2
+    if(b2 is None):
+        b2 = x
+        ib2 = i
+    #smallest
+    elif(x < b2 and b1 is None):
+        #shuffle
+        ib1 = i
+        b1 = x
+    #new smallest    
+    elif(x < b1):
+        ib2 = ib1
+        b2 = b1
+        ib1 = i
+        b1 = x
+    #next smallest    
+    elif(x > b1 and x < b2):
+        b2 = x
+        ib2 = i
+    #########
+    #TOP 1,2,3
+    #Scenario 1: t3 is None
+    if(t3 is None):
+        t3 = x
+        it3 = i
+    #Scenario 2: x > t3 
+    #shuffle back   
+    elif(x > t3):
+        it1 = it2
+        t1 = t2
+        it2 = it3
+        t2 = t3
+        it3 = i
+        t3 = x
+    #Scenario 3: x < t3
+    #check t2 and t1
+    elif (x < t3):
+        #t2?
+        if (t2 is None):
+            t2 = x
+            it2 = i
+        #shuffle back    
+        elif(x > t2):
+            it1 = it2
+            t1 = t2
+            it2 = i
+            t2 = x
+        elif(x < t2 and t1 is None):
+            t3 = x
+            it3 = i
+        elif(x > t1):
+            it1 = i
+            t1 = x
+
+print(input)
+print("Top 3 values >>> ", t1,t2,t3 , "and their index positions =", it1,it2,it3)
+print("Bottom 2 values >>> ", b1,b2, "and their index positions =", ib1,ib2)