Задачи по Python и машинному обучению. Страница 12

data = [(1, 2)]
for n, (x, y) in enumerate(data):
    print(n, x, y)

data = [(1, 2)]
for n, x, y in enumerate(data):
    print(n, x, y, end=" ")

my_list = ['a', 'b']
for idx, val in enumerate(my_list, 3):
    print(idx, val, end=" ")

items = ['a', 'b', 'c']
from itertools import combinations_with_replacement
p = len([* combinations_with_replacement(items, 2)])
print(p)

items = ['a', 'b', 'c']
from itertools import combinations
p = len([*combinations(items, 2)])
print(p)

items = ['a', 'b', 'c']
from itertools import permutations
p = len([*permutations(items, 2)])
print(p)

from itertools import dropwhile
s = [x for x in dropwhile(lambda t: t % 2 == 0, [10, 8, 6, 5, 4, 3])]
print(*s)

from itertools import dropwhile
s = [x for x in dropwhile(lambda t: t % 2 == 0, range(4))]
print(*s)

from itertools import islice
items = [1, 2, 3, 4, 5, 6]
for x in islice(items, 3, None):
    print(x, end="")

from itertools import islice
g = (i**2 for i in range(1, 4))
print(*g[1:3])  # 1
print(*islice(g, 1, 3))  # 2
print(*slice(g, 1, 3))  # 3
print(*g.slice(1, 3))  # 4

from itertools import repeat, chain
class A:
    def __init__(self, x):
        self.x = x
    def __reversed__(self):
        return chain(reversed(self.x), repeat(0, 2))
a = A([1, 2])
print(*reversed(a))

class X:
    def __init__(self, arr):
        self._arr = arr
    def __iter__(self):
        return reversed(self._arr)
x = X([1, 2, 3])
for i in x:
    print(i, end=" ")