[파이썬 기초] 집합

집합

중복을 허용하지 않는다. 순서가 없다.

집합 생성

a_set = set([1,2,3,4,5,6,7,7,7,8,9,9])
a_set

{1, 2, 3, 4, 5, 6, 7, 8, 9}

교집합

a_set = set([1,2,3,4,5,6,7,7,7,8,9,9])
b_set = set([1,5,1,5,2,4,6,7])
a_set&b_set

{1, 2, 4, 5, 6, 7}

a_set.intersection(b_set)

{1, 2, 4, 5, 6, 7}

합집합

a_set = set([1,2,3,4,5,6,7,7,7,8,9,9])
b_set = set([1,5,1,5,2,4,6,7])
a_set|b_set

{1, 2, 3, 4, 5, 6, 7, 8, 9}

a_set.union(b_set)

{1, 2, 3, 4, 5, 6, 7, 8, 9}

차집합

a_set = set([1,2,3,4,5,6,7,7,7,8,9,9])
b_set = set([1,5,1,5,2,4,6,7])
a_set - b_set

{3, 8, 9}

a_set.difference(b_set)

{3, 8, 9}

추가

a_set = set([1,2,3,4,5,6,7,7,7,8,9,9])
a_set.add(5)
a_set.update([11,22,33])
a_set

{1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33}

제거

a_set = set([1,2,3,4,5,6,7,7,7,8,9,9])
a_set.remove(1)
a_set

{2, 3, 4, 5, 6, 7, 8, 9}