Python program to list the difference between two lists.

In this problem given two lists. Our tasks is to display difference between two lists. Python provides set() method. We use this method here. A set is an unordered collection with no duplicate elements. Set objects also support mathematical operations like union, intersection, difference, and symmetric difference.

Example

Input::A = [10, 15, 20, 25, 30, 35, 40]
B = [25, 40, 35] 
Output:
[10, 20, 30, 15]

Explanation

difference list = A - B

Algorithm

Step 1: Input of two arrays.
Step 2: convert the lists into sets explicitly.
Step 3: simply reduce one from the other using the subtract operator.

Example Code

# Python code to get difference of two lists 
# Using set() 
def Diff(A, B):
   print("Difference of two lists ::>")
   return (list(set(A) - set(B))) 

# Driver Code 
A=list()
n1=int(input("Enter the size of the first List ::"))

print("Enter the Element of first List ::")
for i in range(int(n1)):
   k=int(input(""))
   A.append(k)
B=list()
n2=int(input("Enter the size of the second List ::"))
print("Enter the Element of second List ::")
for i in range(int(n2)):
   k=int(input(""))
   B.append(k)
print(Diff(A, B)) 

Output

Enter the size of the first List ::5
Enter the Element of first List ::
11
22
33
44
55
Enter the size of the second List ::4
Enter the Element of second List ::
11
55
44
99
Difference of two lists ::>
[33, 22]