Given a list, print all the unique numbers in any order. Recommended: Please try your approach on {IDE} first, before moving on to the solution. Method 1 : Traversal of list Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics. To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning - Basic Level Course Using traversal, we can traverse for every element in the list and check if the element is in the unique_list already if it is not over there, then we can append it in the unique_list. This is done using one for loop and other if statement which check if the value is in the unique list or not which is equivalent to another for loop. Python
# Python program to check if two
# to get unique values from list
# using traversal
# function to get unique values
def unique(list1):
# initialize a null list
unique_list = []
# traverse for all elements
for x in list1:
# check if exists in unique_list or not
if x not in unique_list:
unique_list.append(x)
# print list
for x in unique_list:
print x,
# driver code
list1 = [10, 20, 10, 30, 40, 40]
print("the unique values from 1st list is")
unique(list1)
list2 =[1, 2, 1, 1, 3, 4, 3, 3, 5]
print("\nthe unique values from 2nd list is")
unique(list2)
Output: the unique values from 1st list is 10 20 30 40 the unique values from 2nd list is 1 2 3 4 5Method 2 : Using Set Using set() property of Python, we can easily check for the unique values. Insert the values of the list in a set. Set only stores a value once even if it is inserted more then once. After inserting all the values in the set by list_set=set(list1), convert this set to a list to print it. Python
# Python program to check if two
# to get unique values from list
# using set
# function to get unique values
def unique(list1):
# insert the list to the set
list_set = set(list1)
# convert the set to the list
unique_list = (list(list_set))
for x in unique_list:
print x,
# driver code
list1 = [10, 20, 10, 30, 40, 40]
print("the unique values from 1st list is")
unique(list1)
list2 =[1, 2, 1, 1, 3, 4, 3, 3, 5]
print("\nthe unique values from 2nd list is")
unique(list2)
Output: the unique values from 1st list is 40 10 20 30 the unique values from 2nd list is 1 2 3 4 5Method 3 : Using numpy.unique Using Pythons import numpy, the unique elements in the array are also obtained. In first step convert the list to x=numpy.array(list) and then use numpy.unique(x) function to get the unique values from the list. numpy.unique() returns only the unique values in the list. Python3
#Ppython program to check if two
# to get unique values from list
# using numpy.unique
import numpy as np
# function to get unique values
def unique(list1):
x = np.array(list1)
print(np.unique(x))
# driver code
list1 = [10, 20, 10, 30, 40, 40]
print("the unique values from 1st list is")
unique(list1)
list2 =[1, 2, 1, 1, 3, 4, 3, 3, 5]
print("\nthe unique values from 2nd list is")
unique(list2)
Output Method #4: Using collections.Counter() Using python import Counter() from collections print all the keys of Counter elements or we print directly by using * symbol. Below is the implementation of above approach. Python3
# Python program to check if two
# to get unique values from list
# importing counter from collections
from collections import Counter
# Function to get unique values
def unique(list1):
# Print directly by using * symbol
print(*Counter(list1))
# driver code
list1 = [10, 20, 10, 30, 40, 40]
print("the unique values from 1st list is")
unique(list1)
list2 = [1, 2, 1, 1, 3, 4, 3, 3, 5]
print("\nthe unique values from 2nd list is")
unique(list2)
# This code is contributed by vikkycirus
Output: the unique values from 1st list is 10 20 30 40 the unique values from 2nd list is 1 2 3 4 5
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Python
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