파이썬 set

a = {1, 1, 2, 3, 3, 4, 5, 5}

print(a)

{1, 2, 3, 4, 5}

print(a[0]) - error : 인덱스가 없다/순서가없다

중복x 순서x

 

a = {}
type(a)

:: dict

a = set()
type(a)

:: set

a = [1, 1, 2, 3, 3, 4, 1, 5]
print(a)

:: [1, 1, 2, 3, 3, 4, 1, 5]

b = set(a)
print(b)

:: {1, 2, 3, 4, 5}

 

a = {1, 2, 3}
b = {2, 3, 4}

print(a.union(b))  # 합집합
print(a.intersection(b)) # 교집합
print(a.difference(b)) # 차집합
print(a.issubset(b)) # 부분집합

:: {1, 2, 3, 4}
:: {2, 3}
:: {1}
:: False