Dev-C++ Hello world doesn't show

Question

I am new to C++. I downloaded and run Dev-C++ and I write and run F9 this:

#include <iostream>
using namespace std;

int main()
{
   cout << "Hello, world!";
   return 0;
}

But no "Hello, world!" is printed, why?

Answer 1

Many IDE users have this problem. The program runs but it closes before you can see its results on the screen. One portable fix is to add this at the bottom of main before you return:

std::cin.get();

That way it will wait for you to enter some text before it exits.

Answer 2

#include <iostream>
using namespace std;

int main()
{
   cout << "Hello, world!";
   getchar();
   return 0;
}

Add getchar() at the end of your program as a simple "pause-method" as consoles seems to close so fast, so you need to "delay" to see your console.

Answer 3

The output is printed to a terminal, and you don't have a newline etc.... very unlikely that you will see it, so

• Add a newline to the output
• make sure you have time to read the output before the terminal window closes (add a sleep or something)
• Don't use using namespace as that is a bad practice and will lead to trouble in your programming.

So like;

#include <iostream>
#include <unistd.h>

int main()
{
   std::cout << "Hello, world!" << std::endl;
   sleep(2);
   return 0;
}