Python find efficiency comparison in list and dict

Reprinted from: http://blog.csdn.net/wzgbm/article/details/54691615

First give a simple example, the time to test the list and dict find:

ImportTime Query_lst = [-60000,-6000,- -,- -,-6,0,6, -, -,6000,60000] LST = [] dic = {} forIinchRange100000000): Lst.append (i) dic[i] =1Start = Time.time () forVinchQuery_lst:ifVinchLst:ContinueEnd1 = Time.time () forVinchQuery_lst:ifVinchDic:ContinueEnd2 = Time.time ()Print "List Search time:%f"% (End1-start)Print "Dict Search Time:%f"% (END2-END1)
  
 

   
  

  
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Operation Result:

List Search time:11.836798
Dict Search time:0.000007

We can see from the above example that the lookup efficiency of list is much lower than the efficiency of dict, for the following reasons:

The storage structure of a list object in Python uses a linear table, so its query complexity is O (n), while the storage structure of the Dict object uses a hash table, which in its best case is an O (1) query complexity.

Python find efficiency comparison in list and dict