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Create a two-way queue
import collections d = collections.deque()
append(Add an element to the right)
import collections d = collections.deque() d.append(1) d.append(2)print(d)#输出:deque([1, 2])
appendleft(Add an element to the left)
import collections d = collections.deque() d.append(1) d.appendleft(2)print(d)#输出:deque([2, 1])
clear(clear the queue)
import collections d = collections.deque() d.append(1) d.clear()print(d)#输出:deque([])
copy(shallow copy)
import collections d = collections.deque() d.append(1) new_d = d.copy()print(new_d)#输出:deque([1])
count(return the number of occurrences of the specified element)
import collections d = collections.deque() d.append(1) d.append(1)print(d.count(1))#输出:2
extend(extend the elements of a list from the right side of the queue)
import collections d = collections.deque() d.append(1) d.extend([3,4,5])print(d)#输出:deque([1, 3, 4, 5])
extendleft (Extend elements of a list from the left side of the queue)
import collections d = collections.deque() d.append(1) d.extendleft([3,4,5])print(d)# # #输出:deque([5, 4, 3, 1])
index (Find the index position of an element)
import collections d = collections.deque() d.extend(['a','b','c','d','e'])print(d)print(d.index('e'))print(d.index('c',0,3)) #指定查找区间#输出:deque(['a', 'b', 'c', 'd', 'e'])# 4# 2
insert (Insert an element at the specified position)
import collections d = collections.deque() d.extend(['a','b','c','d','e']) d.insert(2,'z')print(d)#输出:deque(['a', 'b', 'z', 'c', 'd', 'e'])
pop (get the rightmost element and delete it in the queue)
import collections d = collections.deque() d.extend(['a','b','c','d','e']) x = d.pop()print(x,d)#输出:e deque(['a', 'b', 'c', 'd'])
popleft (get the leftmost element and delete it in the queue)
import collections d = collections.deque() d.extend(['a','b','c','d','e']) x = d.popleft()print(x,d)#输出:a deque(['b', 'c', 'd', 'e'])
remove (delete the specified element)
import collections d = collections.deque() d.extend(['a','b','c','d','e']) d.remove('c')print(d)#输出:deque(['a', 'b', 'd', 'e'])
reverse (queue reversal)
import collections d = collections.deque() d.extend(['a','b','c','d','e']) d.reverse()print(d)#输出:deque(['e', 'd', 'c', 'b', 'a'])
rotate (put the right element to the left)
import collections d = collections.deque() d.extend(['a','b','c','d','e']) d.rotate(2) #指定次数,默认1次print(d)#输出:deque(['d', 'e', 'a', 'b', 'c'])
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