[Python] 순열, 조합

😉 조합

 

from itertools import combinations  # 조합(순서x)

nums=[1,2,3,4]
arr = list(combinations(nums, 3)) 


#출력: [(1, 2, 3), (1, 2, 4), (1, 3, 4), (2, 3, 4)]

 

 

 

😉 순열

 

from itertools import permutations  # 순열(순서 o)

nums=[1,2,3,4]
arr = list(permutations(nums, 3)) 


#출력: [(1, 2, 3), (1, 2, 4), (1, 3, 2), (1, 3, 4), (1, 4, 2), (1, 4, 3), 
#      (2, 1, 3), (2, 1, 4), (2, 3, 1), (2, 3, 4), (2, 4, 1), (2, 4, 3), 
#      (3, 1, 2), (3, 1, 4), (3, 2, 1), (3, 2, 4), (3, 4, 1), (3, 4, 2), 
#      (4, 1, 2), (4, 1, 3), (4, 2, 1), (4, 2, 3), (4, 3, 1), (4, 3, 2)]

 

 

😉 중복 조합

 

from itertools import combinations_with_replacement # 중복 조합

nums=[1,2,3,4]
M=2

for i in combinations_with_replacement(nums, M):
    print(' '.join(map(str,i))) 
    
#출력
1 1
1 2
1 3
1 4
2 2
2 3
2 4
3 3
3 4
4 4

 

 

😉 중복 순열

 

from itertools import product # 중복 순열

nums=[1,2,3,4]
M=2

for i in product(nums,repeat=M):
	print(' '.join(map(str,i))) #int tuple -> string
    
#출력
1 1
1 2
1 3
1 4
2 1
2 2
2 3
2 4
3 1
3 2
3 3
3 4
4 1
4 2
4 3
4 4