B
    gX\;                 @   s  d Z ddlZddlmZ ddlmZmZmZmZm	Z	m
Z
mZmZmZmZmZ ddlZddlmZmZmZ dddd	d
dddddddddddddddddddddd gZd!d Zd<d"dZd#d Zd=d$dZd>d%dZd&d Zefd'dZd(d Zd)d Zd*d Z d+d
 Z!d?d,dZ"d-d Z#d@d.dZ$d/d Z%d0d Z&d1d Z'dAd2dZ(dBd3d Z)dCd4dZ*dDd5d	Z+d6d Z,dEd7dZ-d8d Z.d9d Z/d:d Z0d;d Z1dS )Fa  Imported from the recipes section of the itertools documentation.

All functions taken from the recipes section of the itertools library docs
[1]_.
Some backward-compatible usability improvements have been made.

.. [1] http://docs.python.org/library/itertools.html#recipes

    N)deque)chaincombinationscountcyclefilterfalsegroupbyislicerepeatstarmapteezip_longest)	randrangesamplechoice	all_equalconsume
dotproduct
first_trueflattengrouperiter_exceptncyclesnthnth_combinationpadnonepairwise	partitionpowersetprependquantify#random_combination_with_replacementrandom_combinationrandom_permutationrandom_product
repeatfunc
roundrobintabulatetailtakeunique_everseenunique_justseenc             C   s   t t|| S )a.  Return first *n* items of the iterable as a list.

        >>> take(3, range(10))
        [0, 1, 2]
        >>> take(5, range(3))
        [0, 1, 2]

    Effectively a short replacement for ``next`` based iterator consumption
    when you want more than one item, but less than the whole iterator.

    )listr	   )niterable r/   5lib/python3.7/site-packages/more_itertools/recipes.pyr)   ;   s    c             C   s   t | t|S )a  Return an iterator over the results of ``func(start)``,
    ``func(start + 1)``, ``func(start + 2)``...

    *func* should be a function that accepts one integer argument.

    If *start* is not specified it defaults to 0. It will be incremented each
    time the iterator is advanced.

        >>> square = lambda x: x ** 2
        >>> iterator = tabulate(square, -3)
        >>> take(4, iterator)
        [9, 4, 1, 0]

    )mapr   )Zfunctionstartr/   r/   r0   r'   J   s    c             C   s   t t|| dS )zReturn an iterator over the last *n* items of *iterable*.

        >>> t = tail(3, 'ABCDEFG')
        >>> list(t)
        ['E', 'F', 'G']

    )maxlen)iterr   )r-   r.   r/   r/   r0   r(   \   s    c             C   s,   |dkrt | dd ntt| ||d dS )aX  Advance *iterable* by *n* steps. If *n* is ``None``, consume it
    entirely.

    Efficiently exhausts an iterator without returning values. Defaults to
    consuming the whole iterator, but an optional second argument may be
    provided to limit consumption.

        >>> i = (x for x in range(10))
        >>> next(i)
        0
        >>> consume(i, 3)
        >>> next(i)
        4
        >>> consume(i)
        >>> next(i)
        Traceback (most recent call last):
          File "<stdin>", line 1, in <module>
        StopIteration

    If the iterator has fewer items remaining than the provided limit, the
    whole iterator will be consumed.

        >>> i = (x for x in range(3))
        >>> consume(i, 5)
        >>> next(i)
        Traceback (most recent call last):
          File "<stdin>", line 1, in <module>
        StopIteration

    Nr   )r3   )r   nextr	   )iteratorr-   r/   r/   r0   r   g   s     c             C   s   t t| |d|S )zReturns the nth item or a default value.

        >>> l = range(10)
        >>> nth(l, 3)
        3
        >>> nth(l, 20, "zebra")
        'zebra'

    N)r5   r	   )r.   r-   defaultr/   r/   r0   r      s    
c             C   s   t | }t|dot|d S )z
    Returns ``True`` if all the elements are equal to each other.

        >>> all_equal('aaaa')
        True
        >>> all_equal('aaab')
        False

    TF)r   r5   )r.   gr/   r/   r0   r      s    
c             C   s   t t|| S )zkReturn the how many times the predicate is true.

        >>> quantify([True, False, True])
        2

    )sumr1   )r.   predr/   r/   r0   r       s    c             C   s   t | tdS )zReturns the sequence of elements and then returns ``None`` indefinitely.

        >>> take(5, padnone(range(3)))
        [0, 1, 2, None, None]

    Useful for emulating the behavior of the built-in :func:`map` function.

    See also :func:`padded`.

    N)r   r
   )r.   r/   r/   r0   r      s    c             C   s   t tt| |S )z~Returns the sequence elements *n* times

        >>> list(ncycles(["a", "b"], 3))
        ['a', 'b', 'a', 'b', 'a', 'b']

    )r   from_iterabler
   tuple)r.   r-   r/   r/   r0   r      s    c             C   s   t ttj| |S )zkReturns the dot product of the two iterables.

        >>> dotproduct([10, 10], [20, 20])
        400

    )r9   r1   operatormul)Zvec1Zvec2r/   r/   r0   r      s    c             C   s
   t | S )zReturn an iterator flattening one level of nesting in a list of lists.

        >>> list(flatten([[0, 1], [2, 3]]))
        [0, 1, 2, 3]

    See also :func:`collapse`, which can flatten multiple levels of nesting.

    )r   r;   )ZlistOfListsr/   r/   r0   r      s    	c             G   s&   |dkrt | t|S t | t||S )aG  Call *func* with *args* repeatedly, returning an iterable over the
    results.

    If *times* is specified, the iterable will terminate after that many
    repetitions:

        >>> from operator import add
        >>> times = 4
        >>> args = 3, 5
        >>> list(repeatfunc(add, times, *args))
        [8, 8, 8, 8]

    If *times* is ``None`` the iterable will not terminate:

        >>> from random import randrange
        >>> times = None
        >>> args = 1, 11
        >>> take(6, repeatfunc(randrange, times, *args))  # doctest:+SKIP
        [2, 4, 8, 1, 8, 4]

    N)r   r
   )functimesargsr/   r/   r0   r%      s    c             C   s    t | \}}t|d t||S )zReturns an iterator of paired items, overlapping, from the original

        >>> take(4, pairwise(count()))
        [(0, 1), (1, 2), (2, 3), (3, 4)]

    N)r   r5   zip)r.   abr/   r/   r0   r      s    
c             C   s<   t | tr tdt | | }} t| g| }t|d|iS )zCollect data into fixed-length chunks or blocks.

        >>> list(grouper('ABCDEFG', 3, 'x'))
        [('A', 'B', 'C'), ('D', 'E', 'F'), ('G', 'x', 'x')]

    z+grouper expects iterable as first parameter	fillvalue)
isinstanceintwarningswarnDeprecationWarningr4   r   )r.   r-   rE   rA   r/   r/   r0   r   	  s    

c              g   sn   t | }tdd | D }xN|rhyx|D ]}| V  q(W W q tk
rd   |d8 }tt||}Y qX qW dS )aJ  Yields an item from each iterable, alternating between them.

        >>> list(roundrobin('ABC', 'D', 'EF'))
        ['A', 'D', 'E', 'B', 'F', 'C']

    This function produces the same output as :func:`interleave_longest`, but
    may perform better for some inputs (in particular when the number of
    iterables is small).

    c             s   s   | ]}t |jV  qd S )N)r4   __next__).0itr/   r/   r0   	<genexpr>'  s    zroundrobin.<locals>.<genexpr>   N)lenr   StopIterationr	   )	iterablespendingZnextsr5   r/   r/   r0   r&     s    
c             C   s    t |\}}t| |t| |fS )a  
    Returns a 2-tuple of iterables derived from the input iterable.
    The first yields the items that have ``pred(item) == False``.
    The second yields the items that have ``pred(item) == True``.

        >>> is_odd = lambda x: x % 2 != 0
        >>> iterable = range(10)
        >>> even_items, odd_items = partition(is_odd, iterable)
        >>> list(even_items), list(odd_items)
        ([0, 2, 4, 6, 8], [1, 3, 5, 7, 9])

    )r   r   filter)r:   r.   Zt1Zt2r/   r/   r0   r   1  s    c                s,   t |  t fddtt d D S )a  Yields all possible subsets of the iterable.

        >>> list(powerset([1, 2, 3]))
        [(), (1,), (2,), (3,), (1, 2), (1, 3), (2, 3), (1, 2, 3)]

    :func:`powerset` will operate on iterables that aren't :class:`set`
    instances, so repeated elements in the input will produce repeated elements
    in the output. Use :func:`unique_everseen` on the input to avoid generating
    duplicates:

        >>> seq = [1, 1, 0]
        >>> list(powerset(seq))
        [(), (1,), (1,), (0,), (1, 1), (1, 0), (1, 0), (1, 1, 0)]
        >>> from more_itertools import unique_everseen
        >>> list(powerset(unique_everseen(seq)))
        [(), (1,), (0,), (1, 0)]

    c             3   s   | ]}t  |V  qd S )N)r   )rL   r)sr/   r0   rN   W  s    zpowerset.<locals>.<genexpr>rO   )r,   r   r;   rangerP   )r.   r/   )rV   r0   r   C  s    c          	   c   s   t  }|j}g }|j}|dkrtx| D ]J}y||kr@|| |V  W q$ tk
rl   ||krh|| |V  Y q$X q$W n\xZ| D ]R}||}y||kr|| |V  W qz tk
r   ||kr|| |V  Y qzX qzW dS )a  
    Yield unique elements, preserving order.

        >>> list(unique_everseen('AAAABBBCCDAABBB'))
        ['A', 'B', 'C', 'D']
        >>> list(unique_everseen('ABBCcAD', str.lower))
        ['A', 'B', 'C', 'D']

    Sequences with a mix of hashable and unhashable items can be used.
    The function will be slower (i.e., `O(n^2)`) for unhashable items.

    Remember that ``list`` objects are unhashable - you can use the *key*
    parameter to transform the list to a tuple (which is hashable) to
    avoid a slowdown.

        >>> iterable = ([1, 2], [2, 3], [1, 2])
        >>> list(unique_everseen(iterable))  # Slow
        [[1, 2], [2, 3]]
        >>> list(unique_everseen(iterable, key=tuple))  # Faster
        [[1, 2], [2, 3]]

    Similary, you may want to convert unhashable ``set`` objects with
    ``key=frozenset``. For ``dict`` objects,
    ``key=lambda x: frozenset(x.items())`` can be used.

    N)setaddappend	TypeError)r.   keyZseensetZseenset_addZseenlistZseenlist_addelementkr/   r/   r0   r*   Z  s0    



c             C   s   t tt tdt| |S )zYields elements in order, ignoring serial duplicates

        >>> list(unique_justseen('AAAABBBCCDAABBB'))
        ['A', 'B', 'C', 'D', 'A', 'B']
        >>> list(unique_justseen('ABBCcAD', str.lower))
        ['A', 'B', 'C', 'A', 'D']

    rO   )r1   r5   r=   
itemgetterr   )r.   r\   r/   r/   r0   r+     s    	c             c   s<   y"|dk	r| V  x|  V  qW W n |k
r6   Y nX dS )aX  Yields results from a function repeatedly until an exception is raised.

    Converts a call-until-exception interface to an iterator interface.
    Like ``iter(func, sentinel)``, but uses an exception instead of a sentinel
    to end the loop.

        >>> l = [0, 1, 2]
        >>> list(iter_except(l.pop, IndexError))
        [2, 1, 0]

    Nr/   )r?   Z	exceptionfirstr/   r/   r0   r     s    c             C   s   t t|| |S )a  
    Returns the first true value in the iterable.

    If no true value is found, returns *default*

    If *pred* is not None, returns the first item for which
    ``pred(item) == True`` .

        >>> first_true(range(10))
        1
        >>> first_true(range(10), pred=lambda x: x > 5)
        6
        >>> first_true(range(10), default='missing', pred=lambda x: x > 9)
        'missing'

    )r5   rT   )r.   r7   r:   r/   r/   r0   r     s    c              O   s,   dd | D | dd }tdd |D S )a  Draw an item at random from each of the input iterables.

        >>> random_product('abc', range(4), 'XYZ')  # doctest:+SKIP
        ('c', 3, 'Z')

    If *repeat* is provided as a keyword argument, that many items will be
    drawn from each iterable.

        >>> random_product('abcd', range(4), repeat=2)  # doctest:+SKIP
        ('a', 2, 'd', 3)

    This equivalent to taking a random selection from
    ``itertools.product(*args, **kwarg)``.

    c             S   s   g | ]}t |qS r/   )r<   )rL   poolr/   r/   r0   
<listcomp>  s    z"random_product.<locals>.<listcomp>r
   rO   c             s   s   | ]}t |V  qd S )N)r   )rL   ra   r/   r/   r0   rN     s    z!random_product.<locals>.<genexpr>)getr<   )rA   kwdsZpoolsr/   r/   r0   r$     s    c             C   s*   t | }|dkrt|n|}t t||S )ab  Return a random *r* length permutation of the elements in *iterable*.

    If *r* is not specified or is ``None``, then *r* defaults to the length of
    *iterable*.

        >>> random_permutation(range(5))  # doctest:+SKIP
        (3, 4, 0, 1, 2)

    This equivalent to taking a random selection from
    ``itertools.permutations(iterable, r)``.

    N)r<   rP   r   )r.   rU   ra   r/   r/   r0   r#     s    c                s8   t |  t }ttt||}t  fdd|D S )zReturn a random *r* length subsequence of the elements in *iterable*.

        >>> random_combination(range(5), 3)  # doctest:+SKIP
        (2, 3, 4)

    This equivalent to taking a random selection from
    ``itertools.combinations(iterable, r)``.

    c             3   s   | ]} | V  qd S )Nr/   )rL   i)ra   r/   r0   rN     s    z%random_combination.<locals>.<genexpr>)r<   rP   sortedr   rW   )r.   rU   r-   indicesr/   )ra   r0   r"     s    
c                s@   t | t t fddt|D }t fdd|D S )aS  Return a random *r* length subsequence of elements in *iterable*,
    allowing individual elements to be repeated.

        >>> random_combination_with_replacement(range(3), 5) # doctest:+SKIP
        (0, 0, 1, 2, 2)

    This equivalent to taking a random selection from
    ``itertools.combinations_with_replacement(iterable, r)``.

    c             3   s   | ]}t  V  qd S )N)r   )rL   re   )r-   r/   r0   rN     s    z6random_combination_with_replacement.<locals>.<genexpr>c             3   s   | ]} | V  qd S )Nr/   )rL   re   )ra   r/   r0   rN   	  s    )r<   rP   rf   rW   )r.   rU   rg   r/   )r-   ra   r0   r!     s    c       	      C   s   t | }t|}|dk s ||kr$td}t||| }x*td|d D ]}||| |  | }qFW |dk rr||7 }|dk s||krtg }xj|r|| | |d |d   }}}x.||kr||8 }|||  | |d  }}qW ||d|   qW t |S )a)  Equivalent to ``list(combinations(iterable, r))[index]``.

    The subsequences of *iterable* that are of length *r* can be ordered
    lexicographically. :func:`nth_combination` computes the subsequence at
    sort position *index* directly, without computing the previous
    subsequences.

    r   rO   )r<   rP   
ValueErrorminrW   
IndexErrorrZ   )	r.   rU   indexra   r-   cr^   re   resultr/   r/   r0   r     s(    	 
c             C   s   t | g|S )a  Yield *value*, followed by the elements in *iterator*.

        >>> value = '0'
        >>> iterator = ['1', '2', '3']
        >>> list(prepend(value, iterator))
        ['0', '1', '2', '3']

    To prepend multiple values, see :func:`itertools.chain`.

    )r   )valuer6   r/   r/   r0   r   0  s    )r   )N)N)N)N)N)N)N)NN)N)2__doc__rH   collectionsr   	itertoolsr   r   r   r   r   r   r	   r
   r   r   r   r=   Zrandomr   r   r   __all__r)   r'   r(   r   r   r   boolr    r   r   r   r   r%   r   r   r&   r   r   r*   r+   r   r   r$   r#   r"   r!   r   r   r/   r/   r/   r0   <module>	   sv   4
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