Python 小案例 首字母分类

要求：
1.自己查找一些英文词汇，存储到某个容器类中
2.根据英文词汇的首字母进行分类，类似于手机通讯簿中的快速查找功能
3.根据用户输入的字母，找到该字母开头的所有单词

#coding=utf-8lexicons=["the","be","of","and","A","to","in","he","have","it","that","for","they","I","with","as","not","on","she","at","by","this","we","you","do","but","from","or","which","one","would","all","will","there","say","who","make","when","can"]while True:    startLetter=raw_input("输入一个字母，列出所有以此字母开头的单词:")    if len(startLetter)!=1:        print "必须是一个字母"    else:        reLexicons=[] #结果列表        for x in xrange(len(lexicons)):            lexicon=lexicons[x]            if lexicon[0].lower()==startLetter.lower():#都转为小写后比较  开头字母不区分大小写                reLexicons.append(lexicon)        if len(reLexicons)==0:            print "没有结果"        else:            for x in xrange(len(reLexicons)):                print reLexicons[x]

上面的代码没有走第二步，如下代码 使用字典解决第二步

#coding=utf-8'''边遍历，边构造 key value '''lexicons=["the","be","of","and","A","to","in","he","have","it","that","for","they","I","with","as","not","on","she","at","by","this","we","you","do","but","from","or","which","one","would","all","will","there","say","who","make","when","can"]lexiconDict={}#分类  保存字典中lexiconLen=len(lexicons)for x in xrange(len(lexicons)):    lexicon=lexicons[x]    startLetter=lexicon[0]    dictLexicons=lexiconDict.get(startLetter,[])                #空列表说明没有Key 则添加Key 否则追加Key对应的Value    if len(dictLexicons)==0:        lexiconDict[startLetter]=[lexicons[x]]    else:        dictLexicons.append(lexicons[x])while True:    startLetter=raw_input("输入一个字母，列出所有以此字母开头的单词:")    if len(startLetter)!=1:        print "必须是一个字母"    else:        lexicons=lexiconDict.get(startLetter.lower(),[])        if len(lexicons)==0:            print "没有结果"        else:            for x in lexicons:                print x