python 排序冒泡排序与双向冒泡排序
冒泡排序:
冒泡排序就是每次找出最大(最小)元素,放在集合最前或最后,这是最简单的排序算法
def bubble_sort(collection): #升序排列 length=len(collection) for s in range(length-1):#可以假设只有一个元素的情况,这样可以直接返回 flage=True#应该放在这里,而不是上面 for i in range(length-1-s): if collection[i]>collection[i+1]:#前者大需要换位置,并需要判断他是否是最大的 flage=False collection[i],collection[i+1]=collection[i+1],collection[i] # print("排序第",s+1,"轮之后:",collection)#print()好占时间啊 # i++#i是自动递增的,我竟然写出如此愚蠢的 if flage: break return collection
特点:是稳定的 T(n)=O(n^2) 原地排序
内层循环的操作是O(1)的,共执行n-1轮循环,每轮分别执行(n-1,n-2....1)=(n-1)(n-1+1)/2
双向冒泡排序:
双向冒泡排序又称为:鸡尾酒排序
双向冒泡作为冒泡排序的轻微改进,主要的不同就在于遍历元素时不只有从前到后,而是在遍历到序列的队尾时,按照从后向前在遍历到队头。
以序列(2,3,4,5,1)为例,鸡尾酒排序只需要访问一次序列就可以完成排序,但如果使用冒泡排序则需要四次。但是在随机数序列的状态下,鸡尾酒排序与冒泡排序的效率都很差劲。
def bidirectional_bubble_sort3(collection): length=len(collection) disorder_start_index=0 disorder_end_index=length-1 while disorder_start_index<disorder_end_index: #正序 flage=False #先让初始的两个有序 if collection[disorder_start_index]>collection[disorder_start_index+1]: collection[disorder_start_index],collection[disorder_start_index+1]=collection[disorder_start_index+1],collection[disorder_start_index] for i in range(disorder_start_index+1,disorder_end_index): #一次找两个最大的元素,为什么是两个,因为不用第二次比较,假如比这两个中的第一个大就让第一个向后挪,如果比第一个小,就和第二个比较 if collection[i]>collection[i+1]: collection[i],collection[i+1]=collection[i+1],collection[i] flage=True if collection[i]<collection[i-1]: collection[i],collection[i-1]=collection[i-1],collection[i] disorder_end_index-=2 if collection[disorder_end_index]<collection[disorder_end_index-1]: collection[disorder_end_index],collection[disorder_end_index-1]=collection[disorder_end_index-1],collection[disorder_end_index] for j in range(disorder_end_index-1,disorder_start_index,-1): if collection[j]<collection[j-1]: collection[j],collection[j-1]=collection[j-1],collection[j] flage=True if collection[j]>collection[j+1]: collection[j],collection[j+1]=collection[j+1],collection[j] disorder_start_index+=2 if not flage: break return collection
算法分析:最坏时间复杂度O(n^2) 、平均时间复杂度O(n^2)、最优时间复杂度O(n)
但如果序列在一开始已经大部分排序过的话,会接近。
对比
与冒泡相比,比冒泡快20%,时间是冒泡的80%
详细数据:[-0.01099324226, -0.01499199867, -0.01399159431, -0.01399326324, -0.01499223709, -0.01399183273, -0.01599097252, -0.01499199867, -0.0160036087, -0.01500368118, -0.01399087906, -0.014993667 6, -0.01599144936, -0.014991045, -0.01399230957, -0.01599121094, -0.01401019096, -0.01300311089, -0.01602697372, -0.01500558853, -0.01799058914, -0.01498985291, -0.01596426964, -0.01299071312, -0.01600933075, -0.01598501205, -0.01598405838, -0.01801800728, -0.0170276165, -0.01397919655, -0.01600432396, -0.13593554497, -0.01498842239, -0.01499223709, -0.01497864723, -0.01601624489, -0.01398897171, -0.01598596573, -0.01599144936, -0.01600551605, 0.05896472931, -0.01797199249, -0.01601552963, -0.01200699806, -0.01499462128, -0.0159740448, -0.01597189903, -0.01500415802, -0.01497507095, -0.01597762108, -0.0139913559, -0.01595687866, -0.00696969032, -0.01799035072, -0.01097488403, -0.01895284653, -0.01496243477, -0.01797008514, -0.0159766674, -0.02300024033, -0.0159907341, -0.02098846436, -0.01899337769, -0.008010149, -0.02000403404, -0.01698970795, -0.01698923111, -0.02098751068, -0.01400947571, -0.03299713135, -0.22087359428, -0.0069963932, -0.15491271019, -0.00699687004, -0.01550579071, -0.014991045, -0.01399278641, -0.0089943409, -0.01499080658, -0.04297423363, -0.01499080658, -0.01399040222, -0.01799154282, -0.01499199867, -0.01998782158, -0.01599144936, -0.01299262047, -0.01598978043, -0.01399302483, -0.01399111748, -0.01199412346, -0.01499032974, -0.0169904232, -0.01698660851, -0.01517891884, -0.0129904747, -0.01498866081, -0.01398968697, -0.01742386818, -0.01702928543] 运行了100次,平均运行时间差(bidirectional_bubble_sort3-bubble_sort)(正数代表你是个弟弟)是:-0.01958100796 前者(bidirectional_bubble_sort3)平均运行时间0.06751573801,后者(bubble_sort)平均运行时间0.08709674597,前者约是后者的0.7752倍
与快排相比:是快排的40倍
详细数据:[0.0679602623, 0.06796073914, 0.06896018982, 0.06798624992, 0.06896018982, 0.06895971298, 0.06896018982, 0.068972826, 0.06895947456, 0.06896018982, 0.06698727608, 0.06896114349, 0.06997680 664, 0.06896066666, 0.06794142723, 0.06797409058, 0.06996369362, 0.06894779205, 0.0699737072, 0.06796240807, 0.0689599514, 0.06696033478, 0.06995916367, 0.067943573, 0.06797242165, 0.06894803047, 0.06996655464, 0.06995368004, 0.06894516945, 0.06995940208, 0.06997895241, 0.06897211075, 0.0689599514, 0.06996059418, 0.06997251511, 0.06896066666, 0.06797456741, 0.06994271278, 0.0689458847, 0.06895947456, 0.06995916367, 0.07095837593, 0.06696271896, 0.07195830345, 0.06699585915, 0.07095932961, 0.06895923615, 0.06896018982, 0.06796050072, 0.06794905663, 0.06894779205, 0.06796050072, 0.06897377968, 0.07295536995, 0.0699596405, 0.06796121597, 0.06897592545, 0.06894993782, 0.0709373951, 0.0689599514, 0.06894612312, 0.07094478607, 0.06897330284, 0.06898331642, 0.06896018982, 0.06796145439, 0.06896018982, 0.0699596405, 0.07095837593, 0.06897234917, 0.06796836853, 0.06696081161, 0.06894207001, 0.06794261932, 0.06796050072, 0.0699596405, 0.06895637512, 0.06997203827, 0.06797218323, 0.0689599514, 0.06994652748, 0.06996011734, 0.06895565987, 0.06996059418, 0.0679602623, 0.06997108459, 0.07096338272, 0.06796073914, 0.06995820999, 0.06895947456, 0.06698918343, 0.06798553467, 0.0679731369, 0.06894683838, 0.06894683838, 0.06796240807, 0.06994342804, 0.06796813011, 0.06895875931, 0.0689599514] 运行了100次,平均运行时间差(bidirectional_bubble_sort3-quick_sort2)(正数代表你是个弟弟)是:0.06901133537 前者(bidirectional_bubble_sort3)平均运行时间0.07079039812,后者(quick_sort2)平均运行时间0.00177906275,前者约是后者的39.7908倍
与归并相比:是归并的将近20倍
详细数据:[0.06596302986, 0.06396269798, 0.06496167183, 0.06296300888, 0.06696891785, 0.06696009636, 0.06396341324, 0.06496405602, 0.06996130943, 0.0649638176, 0.06496357918, 0.06296420097, 0.065960 88409, 0.06196498871, 0.06296205521, 0.06596231461, 0.06596207619, 0.06496143341, 0.06396269798, 0.06396341324, 0.06496334076, 0.06496286392, 0.06296300888, 0.06396245956, 0.06396341324, 0.06396436691, 0.06796193123, 0.065959692, 0.06496143341, 0.06296300888, 0.06396269798, 0.06596088409, 0.06596183777, 0.06396245956, 0.06296300888, 0.06496238708, 0.06296253204, 0.0619635582, 0.06498837471, 0.06597709656, 0.06596016884, 0.06496167183, 0.06596231461, 0.06596708298, 0.06594824791, 0.06596112251, 0.06496214867, 0.06596660614, 0.06595754623, 0.06694293022, 0.06396174431, 0.06696128845, 0.06496310234, 0.06694960594, 0.0669362545, 0.06598424911, 0.06396317482, 0.06596112251, 0.06698656082, 0.06597089767, 0.06496024132, 0.06597447395, 0.06598377228, 0.06596159935, 0.06494235992, 0.06496167183, 0.06596207619, 0.06496191025, 0.0649638176, 0.06696105003, 0.06596183777, 0.06496334076, 0.06496286392, 0.06396198273, 0.0649626255, 0.06296253204, 0.06496238708, 0.06496167183, 0.06596207619, 0.0639629364, 0.06396317482, 0.06496405602, 0.06498575211, 0.0659661293, 0.06595015526, 0.06397628784, 0.06495499611, 0.06293916702, 0.06493544579, 0.06596136093, 0.06498217583, 0.06496167183, 0.06596159935, 0.07195830345, 0.06396317482, 0.06396317482, 0.06596207619, 0.06396174431, 0.06796145439, 0.06496310234] 运行了100次,平均运行时间差(bidirectional_bubble_sort3-merge_sort3)(正数代表你是个弟弟)是:0.06517270088 前者(bidirectional_bubble_sort3)平均运行时间0.06887008905,后者(merge_sort3)平均运行时间0.00369738817,前者约是后者的18.6267倍
与希尔排序相比:是希尔排序的20倍
(sort) λ python some_sort.py 详细数据:[0.06496214867, 0.06596159935, 0.06496286392, 0.06596207619, 0.06596207619, 0.06596112251, 0.06596136093, 0.06596660614, 0.06595993042, 0.06596326828, 0.06596112251, 0.06495976448, 0.06595 9692, 0.06696224213, 0.06498074532, 0.06692624092, 0.06395316124, 0.06694364548, 0.0659430027, 0.06797099113, 0.06594872475, 0.06396269798, 0.06598711014, 0.06498837471, 0.06596064568, 0.06395316124, 0.06495904922, 0.06698966026, 0.06594347954, 0.06594467163, 0.06598091125, 0.06594276428, 0.06594419479, 0.06496310234, 0.06895804405, 0.06596207619, 0.06496310234, 0.06496286392, 0.06696081161, 0.0669438839, 0.06593418121, 0.06594896317, 0.06699919701, 0.06696796417, 0.06695199013, 0.06596136093, 0.06498599052, 0.06496667862, 0.0659570694, 0.06391382217, 0.06594276428, 0.06597590446, 0.06693482399, 0.06596422195, 0.06694245338, 0.06696128845, 0.06497645378, 0.06500053406, 0.0659506321, 0.06793618202, 0.06594920158, 0.06596231461, 0.06797528267, 0.06598067284, 0.06594944, 0.06494998932, 0.06796479225, 0.06596183777, 0.06696128845, 0.06696081161, 0.0669798851, 0.06598258018, 0.06399250031, 0.06494641304, 0.0649895668, 0.06396317482, 0.06596374512, 0.06497192383, 0.06594514847, 0.06493616104, 0.06497645378, 0.0669503212, 0.06594324112, 0.06494402885, 0.06694865227, 0.06499385834, 0.06397032738, 0.06497907639, 0.06594586372, 0.0649497509, 0.06598567963, 0.06594824791, 0.0649626255, 0.06596302986, 0.06594586372, 0.06493163109, 0.06696295738, 0.06597995758, 0.06499958038, 0.06696271896] 运行了100次,平均运行时间差(bidirectional_bubble_sort3-shell_sort3)(正数代表你是个弟弟)是:0.06586106062 前者(bidirectional_bubble_sort3)平均运行时间0.06919025183,后者(shell_sort3)平均运行时间0.00332919121,前者约是后者的20.7829倍
与插入排序相比:比插入慢,是其时间的2倍左右
详细数据:[0.03499317169, 0.03396701813, 0.03796577454, 0.03499388695, 0.03595423698, 0.03402686119, 0.03399848938, 0.03696060181, 0.03297901154, 0.03497552872, 0.03296375275, 0.03398108482, 0.03396 248817, 0.03596591949, 0.03400611877, 0.03496527672, 0.03300404549, 0.03499364853, 0.03499746323, 0.03499794006, 0.03396677971, 0.03300309181, 0.0349817276, 0.03496956825, 0.03496623039, 0.04297542572, 0.03200554848, 0.03296232224, 0.03700256348, 0.03296637535, 0.03199267387, 0.03495168686, 0.03296113014, 0.0339653492, 0.03396773338, 0.04295682907, 0.03298091888, 0.03396201134, 0.03394603729, 0.03399896622, 0.03401470184, 0.03497982025, 0.0329682827, 0.03398132324, 0.03697824478, 0.03496456146, 0.032964468, 0.03499603271, 0.03398656845, 0.03500056267, 0.03497743607, 0.03496861458, 0.03198051453, 0.03301119804, 0.03498029709, 0.0329811573, 0.03496718407, 0.03498005867, 0.03297972679, 0.03398108482, 0.03398156166, 0.03398990631, 0.03296685219, 0.0310087204, 0.03398942947, 0.0319647789, 0.03597855568, 0.03496909142, 0.03296422958, 0.03497958183, 0.0349984169, 0.03496170044, 0.03397202492, 0.03300476074, 0.03299379349, 0.03299474716, 0.03499293327, 0.03394889832, 0.03499150276, 0.03497171402, 0.03794336319, 0.0339756012, 0.03396725655, 0.03196263313, 0.03396320343, 0.03501653671, 0.03497958183, 0.03299164772, 0.03298211098, 0.03599739075, 0.03400588036, 0.03201532364, 0.03499317169, 0.03597450256, 0.03496170044, 0.03801369667, 0.0339820385, 0.03498077393, 0.03398084641, 0.03498029709] 运行了100次,平均运行时间差(bidirectional_bubble_sort3-insertion_sort4)(正数代表你是个弟弟)是:0.03445067883 前者(bidirectional_bubble_sort3)平均运行时间0.06767181158,后者(insertion_sort4)平均运行时间0.03322113276,前者约是后者的2.0370倍
与选择排序相比:比选择排序慢,是选择的2倍左右
详细数据:[0.02798295021, 0.03098106384, 0.02998280525, 0.02996516228, 0.03795814514, 0.03196191788, 0.03199958801, 0.03201460838, 0.0299642086, 0.03096485138, 0.03197264671, 0.03399443626, 0.031999 82643, 0.03397583961, 0.03199720383, 0.03199839592, 0.03298139572, 0.03300595284, 0.0359787941, 0.02999973297, 0.03299283981, 0.03298425674, 0.03295087814, 0.03094530106, 0.02994942665, 0.0329785347, 0.03194737434, 0.03298020363, 0.03097820282, 0.02999544144, 0.03301692009, 0.03300237656, 0.03396272659, 0.03398346901, 0.03198122978, 0.03298258781, 0.03200244904, 0.0319814682, 0.03098106384, 0.0300142765, 0.03398036957, 0.03401565552, 0.03099370003, 0.03095555305, 0.03199458122, 0.03099370003, 0.03498530388, 0.03397893906, 0.0319750309, 0.03297185898, 0.03401732445, 0.03198838234, 0.02898311615, 0.08495044708, 0.03097605705, 0.03498649597, 0.03095364571, 0.03195500374, 0.02899241447, 0.03494858742, 0.03295993805, 0.03196334839, 0.03396272659, 0.03295135498, 0.03197288513, 0.03097701073, 0.03300070763, 0.03199863434, 0.03398823738, 0.03297519684, 0.03296017647, 0.03296780586, 0.03399276733, 0.03398513794, 0.03099942207, 0.03196954727, 0.03098726273, 0.03196763992, 0.03496670723, 0.03401255608, 0.03197717667, 0.03097891808, 0.0310177803, 0.03499245644, 0.03198575974, 0.03298282623, 0.03697443008, 0.03396677971, 0.03198218346, 0.0319955349, 0.03196620941, 0.03297662735, 0.03196763992, 0.03096342087, 0.03297567368, 0.03198027611, 0.03296375275, 0.03198623657, 0.0329709053, 0.03398156166] 运行了100次,平均运行时间差(bidirectional_bubble_sort3-select_sort2)(正数代表你是个弟弟)是:0.03293031931 前者(bidirectional_bubble_sort3)平均运行时间0.06903054476,后者(select_sort2)平均运行时间0.03610022545,前者约是后者的1.9122倍