# Time: O(n)# Space: O(n)# Design and implement a TwoSum class. It should support the following operations: add and find.## add - Add the number to an internal data structure.# find - Find if there exists any pair of numbers which sum is equal to the value.## For example,# add(1); add(3); add(5);# find(4) -> true# find(7) -> falseclassTwoSum(object):def__init__(self):self.dic={}defadd(self,number):ifnumbernotinself.dic:self.dic[number]=1else:self.dic[number]+=1deffind(self,value):dic=self.dicfornumindic:if(value-num)indicand(value-num!=numordic[num]>1):returnTruereturnFalse
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