Given two lists, print all the common element of two lists.
Examples:
Input : list1 = [1, 2, 3, 4, 5] list2 = [5, 6, 7, 8, 9] Output : {5} Explanation: The common elements of both the lists are 3 and 4 Input : list1 = [1, 2, 3, 4, 5] list2 = [6, 7, 8, 9] Output : No common elements Explanation: They do not have any elements in common in between them
Method 1:Using Set’s & property
Convert the lists to sets and then print set1&set2. set1&set2 returns the common elements set, where set1 is the list1 and set2 is the list2.
Below is the Python3 implementation of the above approach:
# Python program to find the common elements # in two lists def common_member(a, b): a_set = set (a) b_set = set (b) if (a_set & b_set): print (a_set & b_set) else : print ( "No common elements" ) a = [ 1 , 2 , 3 , 4 , 5 ] b = [ 5 , 6 , 7 , 8 , 9 ] common_member(a, b) a = [ 1 , 2 , 3 , 4 , 5 ] b = [ 6 , 7 , 8 , 9 ] common_member(a, b) |
Output:
{5} No common elements
Method 2:Using Set’s intersection property
Convert the list to set by conversion. Use intersection function to check if both sets have any elements in common. If they have any elements in common, then print the intersection of both the sets.
Below is the Python3 implementation of the above approach:
# Python program to find common elements in # both sets using intersection function in # sets # function def common_member(a, b): a_set = set (a) b_set = set (b) # check length if len (a_set.intersection(b_set)) > 0 : return (a_set.intersection(b_set)) else : return ( "no common elements" ) a = [ 1 , 2 , 3 , 4 , 5 ] b = [ 5 , 6 , 7 , 8 , 9 ] print (common_member(a, b)) a = [ 1 , 2 , 3 , 4 , 5 ] b = [ 6 , 7 , 8 , 9 ] print (common_member(a, b)) |
Output:
{5} No common elements
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