dictionary
dict = {'A' :1,'D' :4,'C' :3,'B' :2}
정렬 -key : sorted(dict.items())
-value : import operator
sorted(dict.items(), key=operator.itemgetter(1))
key,values,items
print :for key,value in dict.items():
print(key,value)
Counter
from collections import Counter
s="{{20,111},{111}}"
a=Counter(s) : Counter({'{': 3, '2': 1, '0': 1, ',': 2, '1': 6, '}': 3})
a.most_common(n=2) : [(',', 9), ('{', 5)]
print :for i,j in dict.items():
print(i,j)
sort
sorted(list, key=lambda x : x[1])
sorted(list, key=lambda x : (x[1],x[1]))
permutation, combination
from itertools import permutations
a = [1,2,3]
permute = permutations(a,2)
print(list(permute))
-> [(1, 2), (1, 3), (2, 1), (2, 3), (3, 1), (3, 2)]
from itertools import combinations
combi = combinations(a,2)
print(list(combi))
-> [(1, 2), (1, 3), (2, 3)]
from itertools import product
list(product(a,repeat=2))
-> [(1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 3), (3, 1), (3, 2), (3, 3)]
map
2차원 리스트 최소, 최대값
min(map(min,data)), max(map(max,data))
[(i,j) for i in range(n) for j in range(n) if data[i][j]==2]
rjust, ljust, zfill
"2".rjust(3,"0")
#"002"
"123".ljust(5,"1")
#"12311"
"2".zfill(3)
#"002"
"123".zfill(8)
#"000000123"
