maxword2.cpp

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#include <iostream>
#include <string>
using namespace std;
#include "worditer.h"
#include "ctimer.h"
#include "prompt.h"

// illustrates nested loops using WordStreamIterator class
// to find the word that occurs most often in a file
// Owen Astrachan, 2/13/96, 4/10/99

int main()
{
    int maxOccurs = 0;
    int wordCount = 0;
    string word,maxWord; 
    string filename = PromptString("enter file name: ");
    WordStreamIterator outer,inner;
    
    outer.Open(filename);         // open two iterators
    inner.Open(filename);
    
    CTimer timer;
    timer.Start();
    for(outer.Init(); outer.HasMore(); outer.Next())
    {  wordCount++;
    }
    timer.Stop();
    double totalTime = timer.ElapsedTime()*wordCount;
    wordCount = 0;
    timer.Reset();
    
    for(outer.Init(); outer.HasMore(); outer.Next())
    {   word = outer.Current();       // current word for comparison
        wordCount++;
        
        int count = 0;                // count # occurrences      
        timer.Start();
        for(inner.Init(); inner.HasMore(); inner.Next())
        {   if (inner.Current() == word)   // found another occurrence
            {   count++;
            }
        }
        if (count > maxOccurs)             // maximal so far
        {   maxOccurs = count;
            maxWord = word;
        }
        timer.Stop();
        if (wordCount % 100 == 0)
        {   cout  << timer.CumulativeTime() << "\tof " << totalTime << endl;
        }
    }
    cout << endl << "word \"" << maxWord << "\" occurs " 
         << maxOccurs << " times" << endl;
    return 0;
}