HackerRank] introducation to sets 셋 (저장용)

문제 보기 

Problem

A set is an unordered collection of elements without duplicate entries.
When printed, iterated or converted into a sequence, its elements will appear in an arbitrary order.

 

Example

>>> print set() set([])

>>> print set('HackerRank') set(['a', 'c', 'e', 'H', 'k', 'n', 'r', 'R'])

 

>>> print set([1,2,1,2,3,4,5,6,0,9,12,22,3]) set([0, 1, 2, 3, 4, 5, 6, 9, 12, 22])

>>> print set((1,2,3,4,5,5)) set([1, 2, 3, 4, 5])

 

>>> print set(set(['H','a','c','k','e','r','r','a','n','k'])) set(['a', 'c', 'r', 'e', 'H', 'k', 'n'])

>>> print set({'Hacker' : 'DOSHI', 'Rank' : 616 }) set(['Hacker', 'Rank'])

 

>>> print set(enumerate(['H','a','c','k','e','r','r','a','n','k'])) set([(6, 'r'), (7, 'a'), (3, 'k'), (4, 'e'), (5, 'r'), (9, 'k'), (2, 'c'), (0, 'H'), (1, 'a'), (8, 'n')])

Basically, sets are used for membership testing and eliminating duplicate entries.

 

set을 이용해서 평균값구하기

def average(array):
	arr.sort()
    print(sum(set(arr))/len(set(arr)))
    return(' ')

if __name__ == '__main__':
    n = int(input())
    arr = list(map(int, input().split()))
    result = average(arr)
    print(result)

 

def average(array):
# your code goes here
    a=set(arr)
    print(sum(a)/len(a))
    return(' ')

if __name__ == '__main__':
    n = int(input())
    arr = list(map(int, input().split()))
    result = average(arr)
    print(result)

def average(array):
    array.sort()
    average = sum(set(array))/len(set(array))
    return average

if __name__ == '__main__':
    n = int(input())
    arr = list(map(int, input().split()))
    result = average(arr)
    print(result)

def average(array):
    x=set(array)
    y=sum(x)
    z=len(x)
    result=y/z
    return result

if __name__ == '__main__':
    n = int(input())
    arr = list(map(int, input().split()))
    result = average(arr)
    print(result)