Python – Unique values Multiplication

This article focuses on one of the operation of getting the unique list from a list that contains a possible duplicates and performing its product. This operations has large no. of applications and hence it’s knowledge is good to have.

Method 1 : Naive method + loop
In naive method, we simply traverse the list and append the first occurrence of the element in new list and ignore all the other occurrences of that particular element. The task of product is performed using loop.

# Python 3 code to demonstrate
# Unique values Multiplication
# using naive methods + loop

# getting Product
def prod(val) :
    res = 1
    for ele in val:
        res *= ele
    return res

# initializing list
test_list = [1, 3, 5, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))

# using naive method + loop
# Unique values Multiplication
# from list
res = []
for i in test_list:
    if i not in res:
        res.append(i)
res = prod(res)

# printing list after product
print ("The unique elements product : " + str(res))

Output :

The original list is : [1, 3, 5, 6, 3, 5, 6, 1]
The unique elements product : 90

Method 2 : Using set() + loop
This is the most popular way by which the duplicated are removed from the list. After that the product of list can be performed using loop.

# Python 3 code to demonstrate
# Unique values Multiplication
# using set() + loop

# getting Product
def prod(val) :
    res = 1
    for ele in val:
        res *= ele
    return res

# initializing list
test_list = [1, 5, 3, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))

# Unique values Multiplication
# using set() + loop
res = prod(list(set(test_list)))

# Unique values Multiplication
# using set() + loop
# printing result
print ("The unique elements product : " + str(res))

Output :

The original list is : [1, 3, 5, 6, 3, 5, 6, 1]
The unique elements product : 90