Get yes/no in console always fails - c++

Question

I'm trying to make a program that will run over and over again, provided the user says yes every time. Unfortunately, it doesn't seem to recognize when I input yes or no into it, and always does the default "Come again?" message. This is the code I'm using to get the input from the console:
bool getYN(){
bool confirmed = 0;
bool answer = 0;
string input;
while(!confirmed){
getline(cin, input, '\n');
transform(input.begin(), input.end(), input.begin(), toupper);
if(input.c_str() == "Y" || input.c_str() == "YES"){ //If the user says yes
confirmed = 1;
answer = 1;
} else if(input.c_str() == "N" || input.c_str() == "NO"){ //If the user says no
confirmed = 1;
answer = 0;
} else { //If the user says something else entirely
printf("\nCome again? (Y/N) ");
};
};
return answer;
};
I have included <string> and <algorithm>. For some reason, it always acts like it's not getting y/yes or n/no when I type them in. It just keeps asking me to answer again.

Answer 1

if(input.c_str() == "Y" || input.c_str() == "YES"){ //If the user says yes
confirmed = 1;
answer = 1;
} else if(input.c_str() == "N" || input.c_str() == "NO"){ //If the user says no
confirmed = 1;
answer = 0;
}
You should not be doing c-string comparisons like this. You're taking the address of a char and comparing against the address of a text-allocated object. Of course the comparison is going to return false.
With c++ strings, simple operator== comparisons are valid:
if(input == "Y" || input == "YES"){ //If the user says yes
confirmed = 1;
answer = 1;
} else if(input == "N" || input == "NO"){ //If the user says no
confirmed = 1;
answer = 0;
}

Answer 2

#include <iostream>
#include <string>
using namespace std; // For speed
int main()
{
bool saidYes = false;
string input;
while (!saidYes)
{
cout << "Input yes or no: ";
getline(cin, input);
if (input == "no" || input == "n" || input == "NO")
{
saidYes = true; // breaks the loop
}
if (input == "y" || input == "Y" || input == "yes" || input == "YES")
{
saidYes = false;
}
}
return 0;
}
You can use the above example to eliminate a huge portion of unnecessary code, I chose not to add the else statement but it will work if you add that here as well.
You can also condense this code even further but this was only intended to be a simple example as to how to better get this working for you!
As it was said above you can use == to compare the strings, if you're coming from certain other languages it can be an annoying change to get used to lol.
I have included string and algorithm. For some reason, it always acts like it's not getting y/yes or n/no when I type them in. It just keeps asking me to answer again.
algorithm is not required for what you're trying to do, and your making the reading and acceptance of the string input much more difficult than it needs to be.
If you look above you'll see the string input; This is going to be your variable that you can use to store the user input string into.
You'll also notice getline(cin, input); This is what you can use to "read" the string that the user enters when they're prompted to.
#Kelvin Shadewing My initial answer was only directed at your Question, this next example is directed to your comment to me below!
So you've got quite a few options but assuming that you want the user to input either yes or no and depending on the input you want to produce a specific result while ensuring that the user is prompted over and over again to input either yes or no all you have to is modify my original answer like so.
#include <iostream>
#include <string>
using namespace std; // For speed
int main()
{
bool saidYes = false;
string input;
while (!saidYes)
{
cout << "Input yes or no: ";
getline(cin, input);
if (input == "no" || input == "n" || input == "NO")
{
saidYes = true;
cout << "you said no" << endl;
/* breaks the loop by changing the
bool (true or false flag) to true, if you want to produce a specific result,
whether it's a simple output statement or a function call you can put it here
*/
}
else if (input == "y" || input == "Y" || input == "yes" || input == "YES")
{
saidYes = true;
cout << "You said yes" << endl;
/* breaks the loop by changing the
bool (true or false flag) to true, if you want to produce a specific result,
whether it's a simple output statement or a function call you can put it here
*/
}
else saidYes = false;
}
return 0;
}

Answer 3

I've modified my code based on the current best answer, but I've also optimized it so that confirmed is no longer necessary.
bool getYN(){
bool answer = 0;
string input;
while(!answer){
getline(cin, input, '\n');
transform(input.begin(), input.end(), input.begin(), toupper);
if(input == "Y" || input == "YES"){
answer = 2;
} else if(input == "N" || input == "NO"){
answer = 1;
} else {
printf("\nCome again? (Y/N) ");
};
};
return answer - 1;
};
Small optimization, sure, but every little bit counts.