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If statements not executing correctly

ctaylor4874 (36)
My first If statement always executes in the studentFeesCalc(char typeOfStudent, int hoursTaken) function, even when I enter a number that is not true in the statement

if (( MIN_HOURS <= hoursTaken <= MAX_HOURS1) && ((typeOfStudent == 'U') || (typeOfStudent == 'u')))

Could someone point out why this is happening? Thank you all, this forum has been a great help as I learn C++.

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#include <iostream>
#include <cmath>
#include <iomanip>
#include <cctype>
using namespace std;

const string TYPE_U = "Undergraduate";
const string TYPE_G = "Graduate";
const string TYPE_N = "Non-Degree Seeking";
const int COST_PER_CREDIT = 465;
const double NON_DEGREE_FEE = 100;
const double RATE1_3 = .03;
const double UNDER_RATE4_9 = .028;
const double UNDER_RATE10_14 = .025;
const double UNDER_RATE15_18 = .022;
const double RATE_OVER = .019;
const double GRAD_RATE4_9 = .027;
const double GRAD_RATE10_14 = .024;
const double GRAD_RATE15_18 = .021;
const double MIN_HOURS = 1;
const double MAX_HOURS1 = 3;
const double MIN_HOURS2 = 4;
const double MAX_HOURS2 = 9;
const double MIN_HOURS3 = 10;
const double MAX_HOURS3 = 14;
const double MIN_HOURS4 = 15;
const double MAX_HOURS4 = 18;
const double MAX_HOURS5 = 18;

double studentFeesCalc(char typeOfStudent, int hoursTaken);
int main()
{
	char studentType;
	int numHours;
	string displayStudentType;
	
	cout << "Student Fees Calculation Program" << endl << endl;
	cout << "Student types choices:" << endl;
	cout << "     U - undergraduate" << endl;
	cout << "     G - graduate" << endl;
	cout << "     N - non-degree seeking" << endl << endl;
	cout << "Enter student type: " ;
	cin >> studentType;
	cout << endl << endl;
	
	cout << "Enter number of credit hours enrolled in: " ;
	cin >> numHours;
	cout << endl << endl;
	
	if ((studentType == 'U') || (studentType == 'u'))
		{
			displayStudentType = TYPE_U;
		}	
	if ((studentType == 'G') || (studentType == 'g'))
		{
			displayStudentType = TYPE_G;
		}
	if ((studentType == 'N') || (studentType == 'n'))
		{
			displayStudentType = TYPE_N;
		}	
		
	
	
	cout << "Student Fees Summary" << endl << endl;
	cout << "     Student Type:" << setw(35) << displayStudentType << endl;
	cout << "     Credit Hours:" << setw(30) << numHours << endl;
	
	studentFeesCalc(studentType, numHours);


	
 cout << endl << endl;
 system ("PAUSE");
 
 return 0;
}
 
double studentFeesCalc(char typeOfStudent, int hoursTaken)
{
	double totalFees;

			if (( MIN_HOURS <= hoursTaken <= MAX_HOURS1) && ((typeOfStudent == 'U') || (typeOfStudent == 'u')))
		{
					totalFees = ((COST_PER_CREDIT * hoursTaken) * RATE1_3);
					cout << "     Rate Used:" << setw(30) << RATE1_3 << endl << endl;
					cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}	
		
		
			else if ((MIN_HOURS2 <= hoursTaken <= MAX_HOURS2 ) && ((typeOfStudent == 'U') || (typeOfStudent == 'u')))
		{	
			      	totalFees = ((COST_PER_CREDIT * hoursTaken) * UNDER_RATE4_9);
					cout << "     Rate Used:" << setw(30) << UNDER_RATE4_9 << endl << endl;
					cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
		
			else if (( MIN_HOURS3 <= hoursTaken <= MAX_HOURS3) && ((typeOfStudent == 'U') || (typeOfStudent == 'u')))
		{
			     	totalFees = ((COST_PER_CREDIT * hoursTaken) * UNDER_RATE10_14);
					cout << "     Rate Used:" << setw(30) << UNDER_RATE10_14 << endl << endl;
					cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
		
			else if (( MIN_HOURS4 <= hoursTaken <= MAX_HOURS4 ) && ((typeOfStudent == 'U') || (typeOfStudent == 'u')))
		{
                    totalFees = ((COST_PER_CREDIT * hoursTaken) * UNDER_RATE15_18);
					cout << "     Rate Used:" << setw(30) << UNDER_RATE15_18 << endl << endl;
					cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
		
			else if (( MAX_HOURS5 < hoursTaken ) && ((typeOfStudent == 'U') || (typeOfStudent == 'u')))
		{
			     	totalFees = ((COST_PER_CREDIT * hoursTaken) * RATE_OVER);
					cout << "     Rate Used:" << setw(30) << RATE_OVER << endl << endl;
					cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}

	


		
			else if (( MIN_HOURS <= hoursTaken <= MAX_HOURS1 ) && ((typeOfStudent == 'G') || (typeOfStudent == 'g')))
		{
                    totalFees = ((COST_PER_CREDIT * hoursTaken) * RATE1_3);
  			        cout << "     Rate Used:" << setw(30) << RATE1_3 << endl << endl;
                    cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
		
			else if (( MIN_HOURS2 <= hoursTaken <= MAX_HOURS2 ) && ((typeOfStudent == 'G') || (typeOfStudent == 'g')))
		{
                totalFees = ((COST_PER_CREDIT * hoursTaken) * GRAD_RATE4_9);
                cout << "     Rate Used:" << setw(30) << GRAD_RATE4_9 << endl << endl;
		        cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
	
			else if (( MIN_HOURS3 <= hoursTaken <= MAX_HOURS3 ) && ((typeOfStudent == 'G') || (typeOfStudent == 'g')))
		{
                totalFees = ((COST_PER_CREDIT * hoursTaken) * GRAD_RATE10_14);
                cout << "     Rate Used:" << setw(30) << GRAD_RATE10_14 << endl << endl;
		        cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
		
			else if (( MIN_HOURS4 <= hoursTaken <= MAX_HOURS4 ) && ((typeOfStudent == 'G') || (typeOfStudent == 'g')))
		{
               totalFees = ((COST_PER_CREDIT * hoursTaken) * GRAD_RATE15_18);
               cout << "     Rate Used:" << setw(30) << GRAD_RATE15_18 << endl << endl;
		       cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
		
		
			else if (( MAX_HOURS5 < hoursTaken ) && ((typeOfStudent == 'G') || (typeOfStudent == 'g')))
		{
			   	totalFees = ((COST_PER_CREDIT * hoursTaken) * RATE_OVER);
		        cout << "     Rate Used:" << setw(30) << RATE_OVER << endl << endl;
				cout << "     Student Fees:" << setw(31) << totalFees << endl;
		}
	
	
	
        	if ((typeOfStudent == 'n') || (typeOfStudent == 'N'))
	     {
     	       cout << fixed;
		       cout << setprecision(2);
		       cout << "     Student Fees:" << setw(25) << NON_DEGREE_FEE << endl;
         }	
}
mpacker (12)
A common mistake, each comparison needs be be written out.

if (( MIN_HOURS <= hoursTaken <= MAX_HOURS1)

Needs to be:

if (( MIN_HOURS <= hoursTaken && hoursTaken <= MAX_HOURS1)
ctaylor4874 (36)
Ah ok, thank you! I wonder why they don't allow it the way I originally had it.
Gamer2015 (810)
well, it works, but not the way you want it...

because of the operator priority and left-to-right opartors for same-level operators:
if((MIN_HOURS <= hoursTaken) <= MAX_HOURS1)

its the same as:
a + b + c
which is equivalent to
((a + b) + c)

the only difference is the operator
Last edited on
obscure (51)
Yes..

(MIN_HOURS <= hoursTaken) return bool (0 or 1)

which it always less than MAX_HOURS1




ctaylor4874 (36)
Gamer2015 that makes a lot of sense, and thank you for breaking it down obscure.
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