//  For CS 350, Spring 2006                                           v. 2/15/06
//  Illustrates:
//    1.  efficient runtime implementation
//    2.  order(1) memory implementation
//    3.  handling eof for several files

#include <iostream>
#include <fstream>

using namespace std;

int main( int argc, char *argv[] )
{

  int     numFiles = argc-1;
  int     matchCt[ numFiles ];
  int     mismatchCt[ numFiles ];
  fstream infile[ numFiles ];
  int     eof[ numFiles ];
  double  nextVal, gold;  // note that no more than 2 values from files are needed at a time
  int     BadFileNameCt = 0;
  int     sumEOFs;

  // Init vars, check for existence of input files
  for ( int i=0; i<numFiles; i++ ) {
    matchCt[ i ] = 0;
    mismatchCt[ i ] = 0;
    eof[i] = 0;
    infile[i].open( argv[i+1], ios::in );
    if ( !infile[i] ) {
      cerr << argv[i+1] << " not a valid filename." << endl;
      BadFileNameCt++;
    } // if
    if ( BadFileNameCt > 0 ) {
      cerr << "program terminated." << endl;
      return 1;
    } // if
  } // for

  // Process data in all files
  while ( sumEOFs < numFiles ) {  // Keep going until eof on all files
    infile[0] >> gold;
    if ( infile[0].fail() ) {
      eof[0] = 1;
      gold = -9999999999.99;  // need a better solution!
    } // if
    for ( int i=1; i<numFiles; i++ ) {
      infile[i] >> nextVal;
      if ( !infile[i].fail() && !infile[0].fail() )  // successfully read values from gold & file i
        if ( fabs( nextVal-gold ) < 0.001 )  // precision decision should be function call
          matchCt[i]++;
        else {
          mismatchCt[i]++;
          // really need more code here to display mismatch values.
          // One way is to build an output string, add to it with
          // each comparison (add blanks for matches, mismatcheed number
          // for mismatches) and only print if there are mismatches.
        } // else
      if ( infile[0].fail() && !infile[i].fail() )  // gold is short
        mismatchCt[i]++;
      if ( !infile[0].fail() && infile[i].fail() )  // file i is short
        mismatchCt[i]++;
      if ( infile[i].fail() )
        eof[i] = 1;
    } // for i
    // count the number of EOFs
    sumEOFs = 0;
    for ( int i=0; i<numFiles; i++ )
      if ( eof[i] )
	sumEOFs++;
  } // while sumEOFs

  // Report
  cout << "Filename   Match Count  Mismatch Count" << endl;
  for ( int i=1; i<numFiles; i++ )
    cout << argv[i+1] << "           "<< matchCt[i] << "               " << mismatchCt[i] << endl;
  
  return 0;

} // main