请教一个vector<string,int>按string怎么排序

请问一个vector<string,int>按string如何排序
#include   <iostream>
#include   <String>
#include   <vector>
#include   <algorithm>

using   namespace   std;

struct   Pair
{
string   word;
int   times;
};
vector <Pair>   word_count;

int&   tms(const   string&   s)
{
for   (unsigned   int   i=0;   i <word_count.size();   i++)
if   (s==word_count[i].word)
return   word_count[i].times;
Pair   p   =   {s,0};
word_count.push_back(p);
return   (word_count.end()-1)-> times;
}

bool   sort_r(const   Pair&   w1,const   Pair&   w2)
{
return   w1-> word <w2-> word;
}//注意这个函数有问题

void   main()
{
//cout < <( "ab "> "ac ") < <endl;
string   buf;
while   (cin> > buf)
{
if   ( "Quit "!=buf)
tms(buf)++;
else
break;
}
sort(word_count.begin(),word_count.end(),sort_r);//请问如何使用？
for   (vector <Pair> ::const_iterator   ptr=word_count.begin();ptr <word_count.end();++ptr)
cout < <ptr-> word < < ":   " < <ptr-> times < <endl;
}

想对vector类型的word_count根据其中string类型的word进行排序，请尽量使用标准库，再加自定义的方法更佳，第一个给出标准库算法者得分。谢谢！

[解决办法]
重载一下Pair结构的比较函数就可以了
[解决办法]
struct MyStruct
{
MyStruct(const string& s, int iTimes):m_strWord(s), m_iTimes(iTimes){}
string m_strWord;
int m_iTimes;
friend bool operator < (const MyStruct& s1, const MyStruct& s2);
};
bool operator < (const MyStruct& s1, const MyStruct& s2)
{
//添加比较规则,
return s2.m_strWord.compare(s1.m_strWord) == 1;
}

vector <MyStruct> word_count;

int& tms(const string& s)
{
for (size_t i= 0; i < word_count.size(); i++)
{
if (s == word_count[i].m_strWord)
return word_count[i].m_iTimes;
}
MyStruct p(s, 0);
word_count.push_back(p);
return (word_count.end()-1)-> m_iTimes;
}

void main()
{
string buf;
while (cin> > buf)
{
if ( "Quit "!=buf)
tms(buf)++;
else
break;
}
sort(word_count.begin(), word_count.end());
vector <MyStruct> ::iterator it = word_count.begin();
for (; it < word_count.end(); it++)
cout < <it-> m_strWord < < ": " < <it-> m_iTimes < <endl;
}
[解决办法]
关注