统计输入单词的个数

struct Pair
{
 string name;
 double val;
};

vector<Pair>pairs;

double& value(const string&s)
{
 for(int i = 0; i < pairs.size(); ++i)
  if( s == pairs[i].name) return pairs[i].val;

 Pair p = {s,0};
 pairs.push_back(p);

 return pairs[pairs.size() - 1].val;
}

int main()
{
 string buf;
 
 while(cin>>buf && buf != "exit") value(buf)++;

 for( vector<Pair>::const_iterator p = pairs.begin(); p!= pairs.end(); ++p)
  cout<<p->name<<":"<<p->val<<"/n";
 
 system("pause");

 return 0;
}