Thread: Homework Help Using While

Hi,

My assignment is to figure out the total time for a group of songs and see how they will fit on a CD. The data are on file songs.dat and looks like this:

300
250
500
570
380
425
275
305
320
450

The time is entered as seconds. After all the data has been read, the application should print a message indicating the time remaining on the CD. The out put should be in the form of a table with colums and headings written on a file.

The chart should look like this:

Song Song Time Total Time
Number Min Sec Min Sec
1 5 10 5 10
2 7 42 12 52
5 4 19 17 11
3 4 33 21 44
4 10 27 32 11
6 8 55 41 6
7 5 0 46 6
"There are 33 minutes and 54 seconds of space left on the 80 minute CD"

Note that the output converts the input from seconds to minutes and seconds.

This is what I have so far:

Code:

#include <iostream>
#include <fstream>
#include <iomanip>

using namespace std;

int main()
{
        int count;
        int song;
        int sec;
        int min;
        int totalSec;
        int totalMin;

        ifstream indata;
        indata.open("songs.dat");

        if (!indata) 
{
cout << "Can't open input file." <<endl;
return 1;
}
indata >> min >> sec;

cout << setw(4) << "Song" << setw(18)
	 << "Song Time" << setw(18) << "Total Time" << endl;
	 
cout << fixed << setw(2)
	 << "Number" << setw(10) << "Minutes" << setw(10) << "Seconds" << setw(10)
	 << "Minutes" << setw(10) << "Seconds" <<endl;
indata >> min >> sec;

I don't know how to get the information into a chart. I know I need to use a while statement, but I'm not sure how. Can anyone help me??

Thanks

Yes, that does help a little bit. But I still don't know how to get the information in the same format as the chart.

I've tried this:

Code:

while(indata)
{
        song++;
        cout << min;
        totalMin = 0;
        count = 0;

But this doesn't work. Can you give me any more clues?

Thank you!

Ok, after another 3 hours, this is what I have:

Code:

#include <iostream>
#include <fstream>
#include <iomanip>
#include <cmath>

using namespace std;

int main()
{
        int songTm_Min;
        int songTm_Sec;
        int total_Time;
        int totalTm_Min;
        int totalTm_Sec;
		int current_Num;
		int totalTm_Min = 0;
		int song_Num;

      
        ifstream indata;
        indata.open("songs.dat");

        if (!indata) 
{
cout << "Can't open input file." <<endl;
return 1;
}

inData >> current_Num;
 
  while (inData)
  {
   // Calculations
   songTm_Min = current_Num / 60; // Calculates the current song's time in Minutes
   songTm_Sec = current_Num % 60; // Calculates the current song's time left in Seconds
   total_Time = total_Time + current_Num; // Calculates the overall Total Time
   totalTm_Min = total_Time / 60; // Calculates the Total Time in Minutes
   totalTm_Sec = total_Time % 60; // Calculates the Total Time left in Seconds
 
   // Print out the results in a format
   cout << setw (4) << song_Num << setw(12) << songTm_Min << setw(10) << songTm_Sec << setw(14) << totalTm_Min << setw(10) << totalTm_Sec << endl;
   song_Num++;
 
   // Repeat Data-in
   inData >> current_Num;
  
   cout <<endl;
   cout << "There are 33 minutes and 54 seconds of space left on the 80 minute CD." <<endl;
  }

Now I am coming up with a couple of errors. The main one being "inData undeclared identifier". Can someone explain to me what the "inData" does? Where do I declare this at? Didn't I declare it already when I wrote: inData >> current_Num;

I'm still working on this assignment. I've made some changes, but now I'm getting an error that my file cannot be opened. Here is my code:

Code:

#include <iostream>
#include <fstream>
#include <iomanip>
#include <cmath>

using namespace std;

int main()
{
        int songTm_Min;
        int songTm_Sec;
        int total_Time;
        int totalTm_Min;
        int totalTm_Sec;
		int current_Num;
		int song_Num;
		
		      
        ifstream cdFile;
        cdFile.open("songs.dat");

		int counter =1;
		int total = 0;
		int cdNow;
if (cdFile) 
{
cout << "Can't open input file." <<endl;
return 1;
        
}
  cdFile >> cdNow;
 
  while (cdFile)
  {

   
   songTm_Min = current_Num / 60; // Calculates the current song's time in Minutes
   songTm_Sec = current_Num % 60; // Calculates the current song's time left in Seconds
   total_Time = total_Time + current_Num; // Calculates the overall Total Time
   totalTm_Min = total_Time / 60; // Calculates the Total Time in Minutes
   totalTm_Sec = total_Time % 60; // Calculates the Total Time left in Seconds
 
	cout << setw(5) <<"Song"; 
	cout << setw(10) <<"             Song Time";
	cout << setw(10) <<"             Total Time\n\n";
	cout << setw(5) <<"Number"; 
	cout << setw(10) <<"        Minutes";
	cout << setw(10) <<" Seconds";
	cout << setw(10) <<"      Minutes";
	cout << setw(10) <<"  Seconds\n";
	cout <<"-----------------------------------------------------\n";

   cout << "There are 33 minutes and 54 seconds of space left on the 80 minute CD." <<endl;
  }
}

How come I can't open my file??

>> if (cdFile)

That evaluates to true if the file opened successfully. Did you mean if (!cdFile)?

THANK YOU!!!!!!!!!!!!!!!