multisetwordcount.cpp

C++编程思想第二版第一册答案

//: C20:MultiSetWordCount.cpp
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
//{L} StreamTokenizer
// Count occurrences of words using a multiset
#include "StreamTokenizer.h"
#include "../require.h"
#include <string>
#include <set>
#include <fstream>
#include <iterator>
using namespace std;

int main(int argc, char* argv[]) {
  requireArgs(argc, 1);
  ifstream in(argv[1]);
  assure(in, argv[1]);
  StreamTokenizer words(in);
  multiset<string> wordmset;
  string word;
  while((word = words.next()).size() != 0)
    wordmset.insert(word);
  typedef multiset<string>::iterator MSit;
  MSit it = wordmset.begin();
  while(it != wordmset.end()) {
    pair<MSit, MSit> p=wordmset.equal_range(*it);
    int count = distance(p.first, p.second);
    cout << *it << ": " << count << endl;
    it = p.second; // Move to the next word
  }
} ///:~