都是一步得出结果，没有把问题分解 from functools import reduce

def str2float(s): b=list(map(deal,s)) fr,bc=sp(b,'.')

return reduce(fix1,fr)+0.1*reduce(fix2,doge(bc))

def deal(i): sum=0 dic={'0':0,'1':1,'2':2,'3':3,'4':4,'5':5,'6':6,'7':7,'8':8,'9':9} if i=='.': return i elif dic.get(i,-1)!=-1: return dic[i]

def doge(lis): ll=[] for i in range(len(lis)): ll.append(lis[len(lis)-1-i]) return ll

def sp(lis,i): for a in range(len(lis)): if lis[a]==i: return lis[:a],lis[a+1:] return None

def fix1(a,b): return a*10+b

def fix2(a,b): return a*0.1+b