diff --git a/data_structures/array/binary_search_infinite_array.py b/data_structures/array/binary_search_infinite_array.py
index 6eff9207..1db83e07 100644
--- a/data_structures/array/binary_search_infinite_array.py
+++ b/data_structures/array/binary_search_infinite_array.py
@@ -23,7 +23,7 @@ def search(arr, val):
     high = 1
 
     while temp < val:
-        low = 0
+        low = high
         high = 2 * high
         temp = arr[high]
 
diff --git a/data_structures/array/duplicate.py b/data_structures/array/duplicate.py
index 1e4f6291..4838b1aa 100644
--- a/data_structures/array/duplicate.py
+++ b/data_structures/array/duplicate.py
@@ -17,13 +17,13 @@ def duplicate(arr):
         if tortoise == hare:
             break
 
-    ptr1 = arr[0]
-    ptr2 = tortoise
-    while ptr1 != ptr2:
-        ptr1 = arr[ptr1]
-        ptr2 = arr[ptr2]
+    tortoise = arr[0]
+
+    while tortoise != hare:
+        tortoise = arr[tortoise]
+        hare = arr[hare]
 
-    return ptr1
+    return hare
 
 
 arr = [3,5,1,2,4,5]
diff --git a/data_structures/array/find_given_sum_in_array.py b/data_structures/array/find_given_sum_in_array.py
index 0aacc5b4..e3adcfcb 100644
--- a/data_structures/array/find_given_sum_in_array.py
+++ b/data_structures/array/find_given_sum_in_array.py
@@ -24,4 +24,4 @@ def find_sum(arr, s):
 
 arr = [15, 2, 4, 8, 9, 5, 10, 23] 
 
-print(find_sum(arr, 6))
+print(find_sum(arr, 6))
\ No newline at end of file
diff --git a/data_structures/array/peak_element.py b/data_structures/array/peak_element.py
index 29d8b1f2..ded661b0 100644
--- a/data_structures/array/peak_element.py
+++ b/data_structures/array/peak_element.py
@@ -6,8 +6,7 @@ def peak(arr, low, high):
     n = len(arr)
 
     while low <= high:
-        mid = low + (high - low) / 2
-        mid = int(mid)
+        mid = (high - low) // 2
         
         if (mid == 0 or arr[mid-1] <= arr[mid]) and (mid == n-1 or arr[mid+1] <= arr[mid]):
             return(arr[mid])
diff --git a/data_structures/array/square_of_sorted_array.py b/data_structures/array/square_of_sorted_array.py
index 1bebb758..68f196b9 100644
--- a/data_structures/array/square_of_sorted_array.py
+++ b/data_structures/array/square_of_sorted_array.py
@@ -1,3 +1,8 @@
+"""
+Find the square of all the numbers of a sorted array such that after finding the square of the sorted array, the
+resultant array containing the squared numbers remains sorted
+"""
+
 def square(arr):
     n = len(arr)
     j = 0
diff --git a/data_structures/deque/deque.py b/data_structures/deque/deque.py
index d578c8e2..85c7dd2c 100644
--- a/data_structures/deque/deque.py
+++ b/data_structures/deque/deque.py
@@ -47,7 +47,7 @@ def get_last(self):
     def size(self):
         return len(self.data)
 
-    def isEmpty(self):
+    def is_empty(self):
         if len(self.data) == 0:
             return True
         return False
@@ -59,7 +59,7 @@ def contains(self, elem):
         
         return False
 
-    def printElems(self):
+    def print_elements(self):
         result = ""
 
         for i in self.data:
diff --git a/data_structures/linked_list/delete_last_occurrence.py b/data_structures/linked_list/delete_last_occurrence.py
index e76f1d9a..80951ab0 100644
--- a/data_structures/linked_list/delete_last_occurrence.py
+++ b/data_structures/linked_list/delete_last_occurrence.py
@@ -1,3 +1,7 @@
+"""
+Delete last occurence of a number in linked list.
+"""
+
 class Node():
 
     def __init__(self, val):