10815 - 安迪的第一个字典 Andy's First Dictionary（stringstream+set+迭代器）

Andy, 8, has a dream - he wants to produce his
very own dictionary. This is not an easy task for
him, as the number of words that he knows is,
well, not quite enough. Instead of thinking up all
the words himself, he has a briliant idea. From
his bookshelf he would pick one of his favourite
story books, from which he would copy out all
the distinct words. By arranging the words in
alphabetical order, he is done! Of course, it is
a really time-consuming job, and this is where a
computer program is helpful.
You are asked to write a program that lists
all the different words in the input text. In this
problem, a word is defined as a consecutive sequence
of alphabets, in upper and/or lower case.
Words with only one letter are also to be considered. Furthermore, your program must be CaSe InSeNsItIvE.
For example, words like “Apple”, “apple” or “APPLE” must be considered the same.
Input
The input file is a text with no more than 5000 lines. An input line has at most 200 characters. Input
is terminated by EOF.
Output
Your output should give a list of different words that appears in the input text, one in a line. The
words should all be in lower case, sorted in alphabetical order. You can be sure that he number of
distinct words in the text does not exceed 5000.


Sample Input
Adventures in Disneyland
Two blondes were going to Disneyland when they came to a fork in the
road. The sign read: "Disneyland Left."
So they went home.


Sample Output
a
adventures
blondes
came
disneyland
fork
going
home
in
left
read
road
sign
so
the
they
to
two
went
were

when

把读到的单词放入set中会自动排序，然后用迭代器按序输出即可，代码如下：

#include <iostream>#include <string>#include <sstream>#include <set>using namespace std;set<string> dict;int main(){    string s,buf;    while(cin>>s)    {        for(int i=0;i<s.length();i++)        {            if(isalpha(s[i]))            s[i]=tolower(s[i]);            else            s[i]=' ';        }        stringstream ss(s);        while(ss>>buf)        {            dict.insert(buf);        }    }    for(set<string>::iterator i=dict.begin();i!=dict.end();++i)    cout<<*i<<endl;    return 0;}