[codility] OddOccurrencesInArray

app.codility.com/programmers/lessons/2-arrays/odd_occurrences_in_array/

OddOccurrencesInArray coding task - Learn to Code - Codility

dict로 홀수의 개수를 세어서 홀수면 그게 정답

def solution(A):
    # write your code in Python 3.6
    d = {}    
    for i in A:
        if i not in d.keys():
            d[i] = 1
        else:
            d[i] += 1
    for i in d.keys():
        if d[i] % 2 == 1 :
            return i