思路：
利用棧實(shí)現(xiàn)代數(shù)式中括號(hào)有效行的的檢驗(yàn)：
代碼：
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class mychain(object): #利用鏈表建立棧，鏈表為父類(lèi) length=0 def __init__(self,value=None,next=None):#創(chuàng)建鏈表，長(zhǎng)度并不包含頭部 self.value=value self.next=next #mychain.length=mychain.length+1 def append(self,value=None): while self.next!=None: self=self.next self.next=mychain(value) mychain.length=mychain.length+1 #追加時(shí)，鏈表長(zhǎng)度增加 def travle(self):#遍歷鏈表 print(self.value) if self.next!=None: self.next.travle() def drop (self,value):#刪除特定值的第一個(gè)匹配節(jié)點(diǎn) while self.next!=None: if self.next.value!=value: self=self.next else: self.next=self.next.next mychain.length=mychain.length-1 #刪除時(shí)，鏈表長(zhǎng)度減小 break def pop(self):#刪除未節(jié)點(diǎn) if self.next!=None:#并不刪除頭結(jié)點(diǎn) while self.next.next!=None: self=self.next self.next=None mychain.length=mychain.length-1#彈出為節(jié)點(diǎn)，并減小長(zhǎng)度，頭結(jié)點(diǎn)不彈出class stock(mychain):#棧類(lèi) bottom=None #棧底 top=None #棧頂 n_count=0 #計(jì)數(shù) def Max(self): #占中最大值 if self.next!=None: tmp = self.next.value while self.next.next!=None: self=self.next if self.next.value>tmp: tmp=self.next.value return tmp else: print('棧為空！') def Min(self):#棧中的最小值 if self.next!=None: tmp = self.next.value while self.next.next!=None: self=self.next if self.next.value<tmp: tmp=self.next.value return tmp else: print('棧為空！') def push(self,value): #壓棧 while self.next != None: self = self.next self.next = mychain(value) stock.top=self.next stock.length=stock.length+1 stock.n_count=stock.n_count+1 def __init__(self,value='',next=None): self.value=value self.next=next stock.bottom=self stock.top=self #stock.n_count=stock.n_count+1 #stock.length=stock.length+1 def append(self,value=''):#取消追加函數(shù) print('請(qǐng)使用Push()!') def pop(self): if self.next!=None:#并不刪除頭結(jié)點(diǎn) while self.next.next!=None: self=self.next self.next=None stock.top=self stock.length=stock.length-1#彈出為節(jié)點(diǎn)，并減小長(zhǎng)度，頭結(jié)點(diǎn)不彈出class solution(object): def validationofbrackets(self,astr=''):#檢驗(yàn)串中的括號(hào)合法性 braketsstock=stock() for i in astr: if i in ['{','(','[']: braketsstock.push(i) else: if i==')': if braketsstock.top.value=='(': braketsstock.pop() else: return False elif i==']': if braketsstock.top.value=='[': braketsstock.pop() else: return False elif i=='}': if braketsstock.top.value=='{': braketsstock.pop() else: return False else: pass print(astr) print(braketsstock.length) if braketsstock.length==0: return True else: return False |
運(yùn)行：
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bstr='([{((({{}})))}]){{}}{{}{}{}[][]()(123)(((sin5)))}'f=solution()print(f.validationofbrackets(bstr)) |
總結(jié)
到此這篇關(guān)于python代數(shù)式括號(hào)有效性檢驗(yàn)的文章就介紹到這了,更多相關(guān)python代數(shù)式括號(hào)有效性檢驗(yàn)內(nèi)容請(qǐng)搜索服務(wù)器之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持服務(wù)器之家！
原文鏈接：https://www.cnblogs.com/wjqsdwm/p/13765413.html
