Fix indentation contains tabs (flake8 E101,W191)

.travis.yml

@@ -5,7 +5,7 @@ before_install: pip install --upgrade pip setuptools
 install: pip install -r requirements.txt
 before_script:
   - black --check . || true
-  - flake8 . --count --select=E9,F4,F63,F7,F82 --show-source --statistics
+  - flake8 . --count --select=E101,E9,F4,F63,F7,F82,W191 --show-source --statistics
 script:
   - scripts/validate_filenames.py  # no uppercase, no spaces, in a directory
   - mypy --ignore-missing-imports .

backtracking/all_combinations.py

@@ -1,9 +1,9 @@
 # -*- coding: utf-8 -*-
 
 """
-	In this problem, we want to determine all possible combinations of k
-	numbers out of 1 ... n. We use backtracking to solve this problem.
-	Time complexity: O(C(n,k)) which is O(n choose k) = O((n!/(k! * (n - k)!)))
+        In this problem, we want to determine all possible combinations of k
+        numbers out of 1 ... n. We use backtracking to solve this problem.
+        Time complexity: O(C(n,k)) which is O(n choose k) = O((n!/(k! * (n - k)!)))
 """
 
 

backtracking/all_permutations.py

@@ -1,9 +1,9 @@
 """
-	In this problem, we want to determine all possible permutations
-	of the given sequence. We use backtracking to solve this problem.
+        In this problem, we want to determine all possible permutations
+        of the given sequence. We use backtracking to solve this problem.
 
-	Time complexity: O(n! * n),
-	where n denotes the length of the given sequence.
+        Time complexity: O(n! * n),
+        where n denotes the length of the given sequence.
 """
 
 
@@ -13,10 +13,10 @@ def generate_all_permutations(sequence):
 
 def create_state_space_tree(sequence, current_sequence, index, index_used):
     """
-	Creates a state space tree to iterate through each branch using DFS.
-	We know that each state has exactly len(sequence) - index children.
-	It terminates when it reaches the end of the given sequence.
-	"""
+        Creates a state space tree to iterate through each branch using DFS.
+        We know that each state has exactly len(sequence) - index children.
+        It terminates when it reaches the end of the given sequence.
+        """
 
     if index == len(sequence):
         print(current_sequence)
@@ -32,7 +32,7 @@ def create_state_space_tree(sequence, current_sequence, index, index_used):
 
 
 """
-remove the comment to take an input from the user 
+remove the comment to take an input from the user
 
 print("Enter the elements")
 sequence = list(map(int, input().split()))

backtracking/all_subsequences.py

@@ -1,9 +1,9 @@
 """
-	In this problem, we want to determine all possible subsequences
-	of the given sequence. We use backtracking to solve this problem.
+        In this problem, we want to determine all possible subsequences
+        of the given sequence. We use backtracking to solve this problem.
 
-	Time complexity: O(2^n),
-	where n denotes the length of the given sequence.
+        Time complexity: O(2^n),
+        where n denotes the length of the given sequence.
 """
 
 
@@ -13,10 +13,10 @@ def generate_all_subsequences(sequence):
 
 def create_state_space_tree(sequence, current_subsequence, index):
     """
-	Creates a state space tree to iterate through each branch using DFS.
-	We know that each state has exactly two children.
-	It terminates when it reaches the end of the given sequence.
-	"""
+        Creates a state space tree to iterate through each branch using DFS.
+        We know that each state has exactly two children.
+        It terminates when it reaches the end of the given sequence.
+        """
 
     if index == len(sequence):
         print(current_subsequence)
@@ -29,7 +29,7 @@ def create_state_space_tree(sequence, current_subsequence, index):
 
 
 """
-remove the comment to take an input from the user 
+remove the comment to take an input from the user
 
 print("Enter the elements")
 sequence = list(map(int, input().split()))

backtracking/sum_of_subsets.py

@@ -1,9 +1,9 @@
 """
-	The sum-of-subsetsproblem states that a set of non-negative integers, and a value M, 
-	determine all possible subsets of the given set whose summation sum equal to given M.
+        The sum-of-subsetsproblem states that a set of non-negative integers, and a value M,
+        determine all possible subsets of the given set whose summation sum equal to given M.
 
-	Summation of the chosen numbers must be equal to given number M and one number can 
-	be used only once.
+        Summation of the chosen numbers must be equal to given number M and one number can
+        be used only once.
 """
 
 
@@ -18,12 +18,12 @@ def generate_sum_of_subsets_soln(nums, max_sum):
 
 def create_state_space_tree(nums, max_sum, num_index, path, result, remaining_nums_sum):
     """
-	Creates a state space tree to iterate through each branch using DFS.
-	It terminates the branching of a node when any of the two conditions 
-	given below satisfy.
-	This algorithm follows depth-fist-search and backtracks when the node is not branchable.
+        Creates a state space tree to iterate through each branch using DFS.
+        It terminates the branching of a node when any of the two conditions
+        given below satisfy.
+        This algorithm follows depth-fist-search and backtracks when the node is not branchable.
 
-	"""
+        """
     if sum(path) > max_sum or (remaining_nums_sum + sum(path)) < max_sum:
         return
     if sum(path) == max_sum:
@@ -41,7 +41,7 @@ def create_state_space_tree(nums, max_sum, num_index, path, result, remaining_nu
 
 
 """
-remove the comment to take an input from the user 
+remove the comment to take an input from the user
 
 print("Enter the elements")
 nums = list(map(int, input().split()))

boolean_algebra/quine_mc_cluskey.py

@@ -1,11 +1,11 @@
 def compare_string(string1, string2):
     """
-	>>> compare_string('0010','0110')
-	'0_10'
-	
-	>>> compare_string('0110','1101')
-	-1
-	"""
+        >>> compare_string('0010','0110')
+        '0_10'
+
+        >>> compare_string('0110','1101')
+        -1
+        """
     l1 = list(string1)
     l2 = list(string2)
     count = 0
@@ -21,9 +21,9 @@ def compare_string(string1, string2):
 
 def check(binary):
     """
-	>>> check(['0.00.01.5'])
-	['0.00.01.5']
-	"""
+        >>> check(['0.00.01.5'])
+        ['0.00.01.5']
+        """
     pi = []
     while 1:
         check1 = ["$"] * len(binary)
@@ -45,9 +45,9 @@ def check(binary):
 
 def decimal_to_binary(no_of_variable, minterms):
     """
-	>>> decimal_to_binary(3,[1.5])
-	['0.00.01.5']
-	"""
+        >>> decimal_to_binary(3,[1.5])
+        ['0.00.01.5']
+        """
     temp = []
     s = ""
     for m in minterms:
@@ -61,12 +61,12 @@ def decimal_to_binary(no_of_variable, minterms):
 
 def is_for_table(string1, string2, count):
     """
-	>>> is_for_table('__1','011',2)
-	True
-	
-	>>> is_for_table('01_','001',1)
-	False
-	"""
+        >>> is_for_table('__1','011',2)
+        True
+
+        >>> is_for_table('01_','001',1)
+        False
+        """
     l1 = list(string1)
     l2 = list(string2)
     count_n = 0
@@ -81,12 +81,12 @@ def is_for_table(string1, string2, count):
 
 def selection(chart, prime_implicants):
     """
-	>>> selection([[1]],['0.00.01.5'])
-	['0.00.01.5']
-	
-	>>> selection([[1]],['0.00.01.5'])
-	['0.00.01.5']
-	"""
+        >>> selection([[1]],['0.00.01.5'])
+        ['0.00.01.5']
+
+        >>> selection([[1]],['0.00.01.5'])
+        ['0.00.01.5']
+        """
     temp = []
     select = [0] * len(chart)
     for i in range(len(chart[0])):
@@ -128,9 +128,9 @@ def selection(chart, prime_implicants):
 
 def prime_implicant_chart(prime_implicants, binary):
     """
-	>>> prime_implicant_chart(['0.00.01.5'],['0.00.01.5'])
-	[[1]]
-	"""
+        >>> prime_implicant_chart(['0.00.01.5'],['0.00.01.5'])
+        [[1]]
+        """
     chart = [[0 for x in range(len(binary))] for x in range(len(prime_implicants))]
     for i in range(len(prime_implicants)):
         count = prime_implicants[i].count("_")