# -*- coding: utf-8 -*-
"""
Created on Sat Oct  8 19:57:46 2022

@author: Roman
"""

import itertools

k = 0
for i in itertools.cycle([1, 2, 3]):
    print(i)
    k += 1
    if k == 10:
        break

for i in itertools.repeat(1, 3):
    print(i)



for i in itertools.accumulate([1, 2, 3, 4, 5]):
    print(i)


for i in itertools.combinations("abcd", 2):
    print(i)
    
for i in itertools.filterfalse(lambda x: x > 5, [4, 5, 6, 7]):
    print(i)
    
def func(a):
    return sum(a)


x = [(1, 2), (2,1), (3, 5), (5, 3)]

for i in itertools.groupby(x, key=func):
    print(list(i))
    
for i in itertools.product([1, 2, 3], [1, 2]):
    print(i)
    
for i in [1, 2, 3]:
    for j in [1, 2]:
        print((i, j))
        
for i in itertools.takewhile(lambda x: x, [1, 2, 3, 0, 5]):
    print(i)
    
    
a = [1, 2, 3, 4]
b = [1, 2, 3]
for i, j in itertools.zip_longest(a, b, fillvalue=-100):
    print(i, j)