Python | Program for counting duplicates in a list of tuples

Counters | Loops | Python Methods and Functions

Examples :

Input: [('a', 'e'), ('b', 'x' ), ('b', 'x'), ('a', 'e'), ('b', 'x')]
Output:
( 'a', 'e') - 2
('b', 'x') - 3

Input: [(0, 5), (6 , 9), (0, 8)]
Output: No Duplicates

Let's see how we can count the duplicates in a list of tuples.

Approach # 1: The Naive Approach

This approach uses two loops to iterate over the elements of the list and check if the first and second element of each element matches any other tuple.

Exit :

 Test Case 1: ('a',' e') - 2 ('b',' x') - 3 Test Case 2: No Duplicates 

Time complexity — O (n) 2

Approach # 2. Using the counter

Counter — it is a container included in the collections module. It is an unordered collection that stores elements and their corresponding counts as a dictionary.

# Python3 code to convert the tuple
# to string

def count (listOfTuple):

 

  flag = False

 

# Add duplicate elements to list

coll_list = [] 

coll_cnt = 0

for t in listOfTuple:

 

# To check if there is duplicate

if t in coll_list: 

  flag = True

continue

 

else :

coll_cnt = 0

for b in listOfTuple:

if b [ 0 ] = = t [ 0 ] and b [ 1 ] = = t [ 1 ]:

coll_cnt = coll_cnt + 1

 

# Print quantity if duplicate element exists

if (coll_cnt & gt;  1 ): 

  print (t, "-" , coll_cnt)

  coll_list.append (t)

 

if flag = = False :

print ( "No Duplicates" )

 
# Driver code

print ( "Test Cas e 1: " )

listOfTuple = [( 'a' , 'e' ), ( ' b' , 'x' ), ( ' b' , 'x' ), 

( 'a' , 'e' ), ( ' b' , 'x' )] 

 
count (listOfTuple)

 

print ( " Test Case 2: " )

listOfTuple = [( 0 , 5 ), ( 6 , 9 ), ( 0 , 8 )]

count (listOfTuple)

# Python3 code to transform a tuple
# to line

import collections

 

def count (listOfTuple):

 

flag = False

val = collections.Counter (listOfTuple)

uniqueList = list ( set (listOfTuple))

 

for i in uniqueList:

if val [i ] & gt; = 2 :

flag = True

print (i, "-" , val [i])

 

  < code class = "keyword"> if flag = = False :

print ( "Duplicate doesn't exist" )

 
# Driver code

listOfTuple = [( ' a' , 'e' ), ( 'b' , ' x' ), ( 'b' , ' x' ), 

( 'a' , ' e' ), ( 'b' , 'x' )] 

count (listOfTuple)

Exit:

 ('b',' x' ) - 3 ('a',' e') - 2 

Time complexity — O (n)

Approach # 3 Using a different dictate

You can create a dictionary, say count_map , and keep the count each tuple as a value.

# Python3 code to convert the tuple
# into a string

def count (listOfTuple):

 

count_map = {}

for i in listOfTuple:

count_map [i] = count_map.get (i, 0 ) + 1

print (count_map)

 
# Driver code

print ( "Test Case 1: " )

listOfTuple = [( 'a' , ' e' ), ( 'b' , 'x' ), ( ' b' , 'x' ), 

  ( 'a' , 'e' ), ( ' b' , 'x' )] 

 
count (listOfTuple)

Exit :

 Test Case 1: {('a',' e'): 2, ('b',' x'): 3 } 

Time complexity — O (n)





Tutorials