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Problem with I/O file

tiara2009 (6)
This is what I did for the input file

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 #include <fstream>
#include <iostream>
using namespace std;

int main( )
{
float distance1 = 2.5 ;
float distance2 = 4.3 ;
float distance3 = 6.2 ;
float distance4 = 8.1 ;
float scale = 0.0001 ;
ofstream outData;

outData.open("E:\\walk.dat");

outData << distance1 << distance2 << distance3 << distance4 << scale;

outData.close( );
system("pause");

return 0;
}


I don't know why the walk.dat was read like this and the result was like this, pls help me ):

For a measurement of 2.54 the first distance is 0 mile(s) long
For a measurement of 0.36 the second distance is 0 mile(s) long
For a measurement of 0.28 the third distance is 0 mile(s) long
For a measurement of 0.1 the fourth distance is 0 mile(s) long
Total mileage for the day is 0 miles

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#include <iostream>
#include <iomanip> 
#include <fstream> 
using namespace std;
int main( )
{
float distance1; 
float distance2; 
float distance3; 
float distance4; 
float scale; 
float totMiles; 
float miles; 
ifstream inData; 
ofstream outData; 
outData<<fixed; 
outData<< showpoint; 
outData << setprecision(1);

inData.open("E:\\walk.dat");
outData.open("E:\\results.dat");

inData >> distance1 >> distance2 >> distance3 >> distance4>> scale;

totMiles = 0.0;

miles = float(int(distance1 * scale * 10.0 + 0.5)) / 10.0;
cout << "For a measurement of " << distance1
<< " the first distance is " << miles
<< " mile(s) long." << endl;
totMiles = totMiles + miles;
miles = float (int(distance2 * scale * 10.0 + 0.5)) / 10.0;
cout << "For a measurement of " << distance2
<< " the second distance is " << miles
<< " mile(s) long." << endl;
totMiles = totMiles + miles;
miles = float(int(distance3 * scale * 10.0 + 0.5)) / 10.0;
cout << "For a measurement of " << distance3
<< " the third distance is " << miles
<< " mile(s) long." << endl;
totMiles = totMiles + miles;
miles = float(int(distance4 * scale * 10.0 + 0.5)) / 10.0;
cout << "For a measurement of " << distance4
<< " the fourth distance is " << miles
<< " mile(s) long." << endl;
totMiles = totMiles + miles;

outData << endl;
cout << "Total mileage for the day is " << totMiles
<< " miles." << endl;
system("pause");
return 0;
}
Last edited on
Chervil (7320)
When you create the output file, all the values are squashed up together, with nothing to separate them.
 
 
    outData << distance1 << distance2 << distance3 << distance4 << scale;


You could put a space, or tab, or a newline character after each value. That way, the program which reads the file will know where one number ends and the next one begins.
tiara2009 (6)
thank you so much
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