calculations with file input creating infinite loops

[swellbo]

Hi! Thanks for reading this. I'm inputting data from a txt file, and I'm trying to add doubles that are assigned to five different integers in the format of


101 38.00
203 124.25
203 30.00
222 65.00
112 74.50
214 97.75
101 87.00
222 102.50
101 21.50
0

with no specified length or numbers. I'm attempting to use a sentinel value read loop but I'm not sure if I'm formatting it correctly. I'm guessing I don't have my loop ordered correctly, or perhaps I'm not assigning variables correctly.

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

using namespace std;
int main ()
{
ofstream a;
ifstream b;
int homeroom;
const int SENTINEL = 0;
double count;
double money;
double money_101, money_112, money_203, money_214, money_222;
b.open ("seniors_rule.txt");
count = 0;
b >> homeroom >> money;
while (homeroom != SENTINEL);
{
	if (homeroom == 101)
	{
		money_101 = count + money;
	}
	else if (homeroom == 112)
	{
		money_112 = count + money;
	}
	else if (homeroom == 203)
	{
		money_203 = count + money;
	}
	else if (homeroom == 214)
	{
		money_214 = count + money;
	}
	else if (homeroom == 222)
	{
		money_222 = count + money;
	}
	b.close ();

}
cout << money_101 << " " << money_112 << " " << money_203 << " " << money_214
		<< " " << money_222;
return 0;
}

Thank you for your feedback, and please let me know if there are adjustments I need to make to the form of my question or other concerns. Thanks!

[Chervil]

Why do you close the input file in the body of the while loop?
And why is only the first pair of values read from the file?

Although the logic is flawed, the semicolon here doesn't help:

    while (homeroom != SENTINEL); // remove semicolon 

[swellbo]

I moved the close file function outside of the loop and tried to apply a function to ensure more than the first value gets read. This is where I'm at now:
code:

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

using namespace std;
int main ()
{
ofstream a;
ifstream b;
int homeroom;
const int SENTINEL = 0;
double count;
double money;
double money_101, money_112, money_203, money_214, money_222;
b.open ("seniors_rule.txt");
count = 0;

while (homeroom != SENTINEL);
{
	while (b >> homeroom >> money);
	{
	if (homeroom == 101)
	{
		money_101 = count + money;
	}
	else if (homeroom == 112)
	{
		money_112 = count + money;
	}
	else if (homeroom == 203)
	{
		money_203 = count + money;
	}
	else if (homeroom == 214)
	{
		money_214 = count + money;
	}
	else if (homeroom == 222)
	{
		money_222 = count + money;
	}
	}

}
b.close ();
cout << money_101 << " " << money_112 << " " << money_203 << " " << money_214
		<< " " << money_222;
return 0;
}

Still getting infinite loops...
thanks

[swellbo]

So instead of getting infinite loops, I'm now getting garbage, which is an improvement, I think? Maybe?

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

using namespace std;
int main ()
{
ofstream a;
ifstream b;
int homeroom;
const int SENTINEL = 0;
double count;
double money;
double money_101, money_112, money_203, money_214, money_222;
b.open ("seniors_rule.txt");


if (homeroom != SENTINEL)
{
	while (b >> homeroom >> money);
	{
	if (homeroom == 101)
	{count = 0;
		money_101 = count + money;
	}
	else while (homeroom == 112)
	{count = 0;
		money_112 = count + money;
	}
	while (homeroom == 203);
	{count = 0;
		money_203 = count + money;
	}
	while (homeroom == 214);
	{count = 0;
		money_214 = count + money;
	}
	while (homeroom == 222);
	{count = 0;
		money_222 = count + money;
	}
	}

}
b.close ();
cout << money_101 << " " << money_112 << " " << money_203 << " " << money_214
		<< " " << money_222;
return 0;
}

[Chervil]

The accumulators money_101 etc. should be initialised to zero.

This line should not have a semicolon:

	while (b >> homeroom >> money);

[swellbo]

ok, so adjusting based on feedback, I have

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

using namespace std;
int main ()
{
ofstream a;
ifstream b;
int homeroom;
const int SENTINEL = 0;
double count;
double money;
double money_101 = 0, money_112 = 0, money_203 = 0, money_214 = 0, money_222 = 0;
b.open ("seniors_rule.txt");


while (b >> homeroom >> money);


{
	count = 0;
	while (homeroom != SENTINEL)
	{
	while (homeroom == 101)
	{
		count = count + money;
		money_101 = count;
	}
	while (homeroom == 112)
	{
		count = 0;
		count = count + money;
		money_112 = count;
	}
	while (homeroom == 203)
	{
		count = 0;
		count = count + money;
		money_203 = count;
	}
	while (homeroom == 214)
	{
		count = 0;
		count = count + money;
		money_214 = count;
	}
	while (homeroom == 222)
	{
		count = 0;
		count = count + money;
		money_222 = count;
	}
	}

}
b.close ();
cout << money_101 << " " << money_112 << " " << money_203 << " " << money_214
		<< " " << money_222;
return 0;
}

[Chervil]

For the third time (do you read my posts?)

This line should not have a semicolon:

    while (b >> homeroom >> money);

Also, after correcting that error, that is the only while loop which is needed. I see the word "while" seven times in the latest version, which is six times too many. The others should be if/else, or maybe a switch/case.