word freq and length sorting.. need help.. stuck..

[rehet]

hye.. i really need ur guys help.. im stuck.. i want to count the word freq and print them according to the word length.. > the longest be output first..
ouh.. and my input must be alphabet or alhabet+numeric only..

here what i did so far..

#include <iostream>
#include <string>
#include <map>
using namespace std;
class Cmp : public std::binary_function<std::string,std::string,bool> {
public:
  bool operator()(const std::string& s1, const std::string& s2){ //????
  }
};
//typedef std::map<std::string, int, Cmp> MAP;

typedef enum {s1, s2} STATUS;
struct Count {
    int N;
    Count() : N(0) {}
    operator int() { return N; }
    void operator++() { N++; }
};
typedef map<string,Count> Map;

int main(void){
  char c;
  map<string,Count> m;
  std::string  buffer;
    STATUS status=s1;
//    while( cin >> str ) stringCounts[str]++; 
  while(std::cin >> c){

    switch(status){
    case s1:
      if(isalpha(c)){
//	m[string]++;
    buffer=c;
	status=s2;
	    
      }
      break;
    case s2:
      if(isalnum(c)){
	buffer+=c;
      }else{
	//std::cout << s1 << s2 << std::endl;
	
	std::cout << c << buffer << std::endl;
	status=s1;
      }

      break;
    }
  }
  if(status=s2){

Map::iterator i = m.begin();
    while ( i != m.end() ) {
      cout << i->first << ':'
           << i->second << endl;
      ++i;
   std::cout << c << buffer << std::endl;
  }


}    
  return 0;
}

can you guys please help me.