Loops

[daddymomo]

I'm trying to write a program that repeats a block of code as long as the user indicates they want to. I've been trying to make one using this code but I keep getting "[Error] ISO C++ forbids comparison between pointer and integer".
Error is the "stop" in if condition.

  #include <iostream>
using namespace std;

int main() {
	char name;
	char stillEntering = true;
	cout << "Enter name or stop: ";
	cin >> name;
	while (stillEntering) {
		cout << name;
		if (name == "stop")
		stillEntering = false;
	}
	return 0;
}

[deleted account xyzzy]

Change char stillEntering to bool.

[Ganado]

That's an issue, but that's not the issue.

Add
#include <string>

and change

char name; to string name;

A char is a single character (byte). A string is a... string... of characters (like an array with some bells and whistles).

Third issue: You never ask for user input within your loop, so your loop will either only run once, or be infinite.
Fourth issue: Line 12 should be indented by one more level.

[daddymomo]

Thanks, those fixed the error. I need help with one more thing tho.
Now when I enter a name it goes into an infinite loop. How do I make it that whenever I enter a name it shows the name then asks me for input again till I input stop then it stops?

[coder777]

name is a single char and "stop" is a string. You cannot compare them (like this). You probably want this:

  #include <iostream>
using namespace std;

int main() {
	char name[100]; // Reasonable large c-string
	char stillEntering = true;
	cout << "Enter name or stop: ";
	cin >> name;
	while (stillEntering) {
		cout << name;
		if (0 == strcmp(name, "stop")) // Note: do not compare c-string directly. This would be a pointer comparison not the content.
		stillEntering = false;
	}
	return 0;
}

[Ganado]

. How do I make it that whenever I enter a name it shows the name then asks me for input again till I input stop then it stops?

You never ask the user for more input. Use cin >> name within your loop (and use cout to let the user know they need to enter something).

Consider a do-while loop.

do
{
    cout << "Enter name: ";
    string name;
    cin >> name;
    if (name == "stop")
    {
        stillEntering = false;
    }
    else
    {
        cout << "Hello, " << name << '\n';
    }

} while (stillEntering);

If you want to use name outside of the loop, then you should probably use two different variables (one for the input, and one to store the name itself).

[deleted account xyzzy]

#include <iostream>
#include <string>

int main()
{
   std::string name;

   while (true)
   {
      std::cout << "Enter name or stop: ";
      std::cin >> name;

      if (name == "stop")
         break;  // exit the loop

      std::cout << name << '\n';
   }
}

Enter name or stop: Fred
Fred
Enter name or stop: Manny
Manny
Enter name or stop: Billy Joe Bob
Billy
Enter name or stop: Joe
Enter name or stop: Bob
Enter name or stop: Stop
Stop
Enter name or stop: STOP
STOP
Enter name or stop: stop

[daddymomo]

Thank you @George P, that was what I was trying to make.
Thank you all for the guidance and information too, much appreciated.

[deleted account xyzzy]

An advanced form of a while loop:

#include <iostream>
#include <string>

int main()
{
   std::string name;

   while (std::cout << "Enter name or stop: " &&
          std::cin >> name &&
          name != "stop")
   {
      std::cout << name << '\n';
   }
}

Enter name or stop: Fred
Fred
Enter name or stop: Manny
Manny
Enter name or stop: Billy Joe Bob
Billy
Enter name or stop: Joe
Enter name or stop: Bob
Enter name or stop: Stop
Stop
Enter name or stop: STOP
STOP
Enter name or stop: stop

[deleted account xyzzy]

As you saw retrieving string input that contains spaces doesn't quite work with std::cin. Use std::getline instead to read the entire line of input:

#include <iostream>
#include <string>

int main()
{
   std::string name;

   while (true)
   {
      std::cout << "Enter name or stop: ";
      
      // retrieve ALL the input, including spaces
      // https://www.cplusplus.com/reference/string/string/getline/
      std::getline(std::cin, name);

      if (name == "stop")
         break;  // exit the loop

      std::cout << name << '\n';
   }
}

Enter name or stop: Fred
Fred
Enter name or stop: Billy Joe Bob
Billy Joe Bob
Enter name or stop: stop

Using std::getline and std::cin together does have other problems you will discover. That's another lesson for later.

[seeplus]

#include <iostream>
#include <string>

int main() {
	for (std::string name; (std::cout << "Enter name or stop to terminate: ") && std::getline(std::cin, name) && name != "stop"; std::cout << name << '\n');
}

[Ganado]

Thanks I hate it.
:)

[deleted account xyzzy]

Yes, seeplus, that is possible, but DAYUM! That is using a nuke to swat a fly. My advanced while loop is bad enough.

That for loop is sufficiently weird enough that I filed it away for future coding horror shows. :Þ

[deleted account xyzzy]

For purposes of being semi-readable I might add some judicious whitespace:

#include <iostream>
#include <string>

int main()
{
   for (std::string name; 
        (std::cout << "Enter name or stop to terminate: ") && std::getline(std::cin, name) && name != "stop";
        std::cout << name << '\n');
}

At least to me it makes it easier to understand the illogic of the loop.

And enclosing the std::cout statement in parentheses is something I should have remembered!

*annoyed grunt!*