wordcount.cpp

来自「C语言数值算法程序大全（第二版）,课本文件」· C++ 代码 · 共 37 行

//: C07:WordCount.cpp
// From "Thinking in C++, 2nd Edition, Volume 2"
// by Bruce Eckel & Chuck Allison, (c) 2003 MindView, Inc.
// Available at www.BruceEckel.com.
// Count occurrences of words using a map
#include "../require.h"
#include <string>
#include <map>
#include <iostream>
#include <fstream>
using namespace std;

class Count {
  int i;
public:
  Count() : i(0) {}
  void operator++(int) { i++; } // Post-increment  
  int& val() { return i; }
};

typedef map<string, Count> WordMap;
typedef WordMap::iterator WMIter;

int main(int argc, char* argv[]) {
  char* fname = "WordCount.cpp";
  if(argc > 1) fname = argv[1];
  ifstream in(fname);
  assure(in, fname);
  WordMap wordmap;
  string word;
  while(in >> word)
    wordmap[word]++;
  for(WMIter w = wordmap.begin(); w != wordmap.end(); w++)
    cout << (*w).first << ": "
      << (*w).second.val() << endl;
} ///:~