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std::cin not resetting in loop

Majeek (28)
Whenever I enter an incorrect answer (main()) then it keeps looping and having this output without stopping to std::cin. Usually std::getline would fix this but I can't do that sense it's integers and not strings.

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#include <iostream>
#include <string>
#include <math.h>

int Check();
void PrintOut(int Quotient, int Remainder);

double Minutes;

int main(){
	while(true){
		std::cout << "How many minutes?: ";
		std::cin >> Minutes;
		if(std::cin.fail()){
			std::cout << "Enter a number, try again.\n\n";
		}
		else{
			break;
		}
	}
	Check();
	return 0;
}


Output:

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How many minutes?
Enter a Number try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.
How many minutes? Enter a number, try again.

This will keep looping

Last edited on
jlb (4973)
How are you clearing the error flag? Once the stream enters an error state it will stay in the error state until the error is cleared and any offending data is removed from the input buffer.

Cheddar99 (103)
Maybe something like this?

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#include <iostream>
#include <math.h>
#include <limits>

int Check();
void PrintOut(int Quotient, int Remainder);

double Minutes;

int main(){
	while(true)
	{
	std::cout << "How many minutes?: ";
	std::cin >> Minutes;

	    if(std::cin.fail())
	    {
	    std::cout << "Enter a number, try again.\n\n";
	    std::cin.clear();
            std::cin.ignore(std::numeric_limits<std::streamsize>::max(),'\n');
	    }
	    else
            {
	    break;
	    }
	}

	// Check();

return 0;
}


Not sure what the "Check()" function is meant to do as you haven't defined it, so commented out for now so it compiles.
Last edited on
Majeek (28)
My full code is here (I finished thanks to your code)
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#include <iostream>
#include <math.h>
#include <limits>

int Check();
void PrintOut(int Quotient, int Remainder);

double Minutes;

int main(){
	while(true)
	{
	std::cout << "How many minutes?: ";
	std::cin >> Minutes;
	    if(std::cin.fail())
	    {
	     std::cout << "Enter a number, try again.\n\n";
	     std::cin.clear();
             std::cin.ignore(std::numeric_limits<std::streamsize>::max(),'\n');
	    }
	    else
            {
	    break;
	    }
	}
Check();
return 0;
}

int Check(){
	int Remainder;
	double Quotient;
	Remainder = remainder(-Minutes, -60);
	Quotient = Minutes / 60;
	PrintOut(Quotient, Remainder);
	return 0;
}

void PrintOut(int Quotient, int Remainder){
	if(Quotient == 1){
		std::cout << Quotient << " hour and " << Remainder << " minutes.";
	}
	else if(Quotient > 1){
		std::cout << Quotient << " hours and " << Remainder << " minutes.";
	}
	return;
}
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