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Sentinel Value and If statements

BeginnerCoder123 (12)
Hello! I am a beginner coder and I am stuck on sentinel values. The problem is that I cannot get the code to move on to the else part of the if statement when the if statement is false. I have marked the code that is giving me the problem. Any tip on going forward would be helpful. Thank you. 

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#include <iostream>
#include <string>


using namespace std;


const int USD = 0;
const int EUR = 1;
const int GBP = 2;
const int INR = 3;
const int AUD = 4;
const int CAD = 5;
const int ZAR = 6;
const int NZD = 7;
const int JPY = 8;


//Outputs a menu of currency types for user, returning a constant value
// as defined above representing the selected currency.
int getUserSelection()
{
	int selection;

	cout << "Available currencies for conversion: " << endl;

	cout << "(1) Euros" << endl;
	cout << "(2) Great Britan Pounds" << endl;
	cout << "(3) Indian Rupees" << endl;
	cout << "(4) Australian Dollars" << endl;
	cout << "(5) Canadian Dollars" << endl;
	cout << "(6) South African Rands" << endl;
	cout << "(7) New Zealand Dollars" << endl;
	cout << "(8) Japanese Zen" << endl;

	cout << "Enter the number of the desired currency to convert: ";

	cin >> selection;

	return selection;
}

//Converts the numeric type to a String representation.
//Use this to output a String representation of the type.
string convertTypeToString(int type)
{
	switch (type)
	{
	case USD:
		return "US Dollars";

	case EUR:
		return "Euros";

	case GBP:
		return "Great Britan Pounds";

	case INR:
		return "Indian Rupees";

	case AUD:
		return "Australian Dollars";

	case CAD:
		return "Canadian Dollars";

	case ZAR:
		return "South African Rands";

	case NZD:
		return "New Zealand Dollars";

	case JPY:
		return "Japanese Zen";
	}

	return "";
}


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

{
	double amount{};
	while (amount != -1)
		{
			int userSelection = getUserSelection();
			string selectionAsAString = convertTypeToString(userSelection);
			cout << "You entered " << selectionAsAString << endl;
			double usDollars{};
			cout << "Please enter an amount to be converted: (enter -1 to stop)" "\n";
			cin >> amount;
			if (-1) // This is what is giving me problems.
	        	{
				return 0;
			}
			else
			{
				cout << "Thank you. " "\n";
			}
			double conversionFactor{};
			if (userSelection == EUR)
				conversionFactor = 1.08611;
			if (userSelection == GBP)
				conversionFactor = 1.44476;
			if (userSelection == INR)
				conversionFactor = 0.01495;
			if (userSelection == AUD)
				conversionFactor = 0.69864;
			if (userSelection == CAD)
				conversionFactor = 0.70112;
			if (userSelection == ZAR)
				conversionFactor = 0.05999;
			if (userSelection == NZD)
				conversionFactor = 0.65371;
			if (userSelection == JPY)
				conversionFactor = 0.00850;
			if (userSelection == EUR)
				usDollars = amount * conversionFactor;
			if (userSelection == GBP)
				usDollars = amount * conversionFactor;
			if (userSelection == INR)
				usDollars = amount * conversionFactor;
			if (userSelection == AUD)
				usDollars = amount * conversionFactor;
			if (userSelection == CAD)
				usDollars = amount * conversionFactor;
			if (userSelection == ZAR)
				usDollars = amount * conversionFactor;
			if (userSelection == NZD)
				usDollars = amount * conversionFactor;
			if (userSelection == JPY)
				usDollars = amount * conversionFactor;
			cout << "Your converted currency is: " << usDollars << " US dollars." "\n";
			cout << "Continue? (Y/N)" "\n";
			if ('Y')
			{
				getUserSelection;
			}
			else
			{
				return 1;
			}

			cin.ignore();
			cin.get();
		
		}
}
jonnin (11441)
if ('Y')
says "if the letter Y is not zero"
Y is not zero. It is always true.
you want if (something == 'Y')
whatever variable you read in for yes/no

all c++ conditions are explicit, unlike math. And the default of single value terms is whether they are zero or not.
Last edited on
seeplus (6597)
L93

 
 
if (amount == -1)


Note that == means equality comparison and = means assignment.

Also similar at L136

You need to specify what it is being compared with.
Last edited on
BeginnerCoder123 (12)
Thank you so much guys, this was very helpful!
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