Hello World C++ - c++

Every time I try and run the Simple Hello World program in C++, I build it and it says nothing to build for FirstProject. The code looks correct, I'm using MinGW as my compiler, etc. Every time I try to run the program, instead of printing the output, it just terminates. Anyone have a clue?
#include <iostream>
using namespace std;
int main() {
cout << "!!!Hello World!!!" << endl; // prints !!!Hello World!!!
return 0;
}

try these commands:
g++ -o hello_world.exe hello_world.cpp
./hello_world.exe
MinGW works same as gcc on linux so all commands which work on linux should work on MinGW

In cygwin, the following steps should work.
Save the contents to file HelloWorld.cc.
Go to the directory where you saved the file.
Execute make HelloWorld
Execute ./HelloWorld.exe
If that doesn't work, something is really not right.

Are you running it from the command line or an IDE? Sometimes an IDE will open a terminal and close it too fast for you to see, or you'll just see a flash. Try running it from the command line so you'll be able to see if it printed anything before exiting the program.

Tried and tested using MinGW in windows 10 command prompt.
#include <iostream>
using namespace std;
int main()
{
cout<<"Hello, World!"<<endl;
system("pause");
return 0;
}
Image of command prompt output

Save the contents to file HelloWorld.cpp
Go to the directory where you saved the file.
Execute make HelloWorld
Execute ./HelloWorld.exe

Related

C++, Nothing in the output [duplicate]

This question already has answers here:
Why do I get no output for very simple Hello World program?
(7 answers)
Closed 6 months ago.
I am new to C++ and coded my first main.cpp but I got an error, not exactly an error, it is a logical error, I guess because I wrote the following code:
#include <iostream> // including the iostream
using namespace std; // using the std namespace
int main() { // starting the main function
cout << "Hello World!" << endl; // My favorite line of code in all the of languages
return 0; // returning 0 to stop the function execution
}
In the terminal I expected
C:\Users\DELL\Desktop> g++ main.cpp
Hello World!
C:\Users\DELL\Desktop>
But it is just showing:
C:\Users\DELL\Desktop> g++ main.cpp
C:\Users\DELL\Desktop>
No output is coming, but when I try in Code::Blocks, it is working just fine! In vscode terminal, the same problem but when I run the file, it is working again! Why is it not working? I tried it in Command Prompt, installed the Windows Terminal, and tried it in that also (keeping the terminal as Command Prompt, cause I don't know what PowerShell is and how to use it) but any method is not working.
Please tell me what to do, I am new to c++ and know only some things amount it.
The command g++ main.cpp creates the file a.out or a.exe. After that file is created you need to run it by the command ./a.out on Linux and Mac or a.exe on Windows.
It's pretty simple, after g++ "file.cpp", you get an output file in your current working directory, which is the executable. C++ is compiled, not interpreted.
That output file is the executable, which by default will be "a.out", with gcc/g++. You can use the option "-o" to specify the output directory.
g++ main.cpp will compile the file and produce a.exe, you just need to type a.exe in the terminal and it will print Hello World!.

Notepad++ NppExec console warning, need explanation "C++"

I've tried using Notepad++ to code c++ and followed a few tutorials on youtube, here's what I did:
-Installed gcc/g++ compiler using mingw64
-Installed NppExec plugin on N++
-Typed in the following compilier script and saved as C++:
NPP_SAVE cd $(CURRENT_DIRECTORY) g++ $(FILE_NAME) cmd /c $(CURRENT_DIRECTORY)\program.exe
Anyways whenever compiling a program, for example a simple program
#include <iostream>
using namespace std;
int main(){
cout << "Online\n";
system("pause"); //So that cmd doesn't disappear immeadiately on running.
return 0;
}
The console displays the following warning:
"C:\Users\pc\Desktop\Courses\Projects\C\program.exe' is not recognized as an internal or external command, operable program or batch file."
My question is, When I run the program on cmd, it runs perfectly but the error displayed during linking says that the folder does not exist in %PATH%
Any explanation?
Thank you!
Ok so, what I basically did was change the script,
cmd /c $(CURRENT_DIRECTORY)\program.exe
To be later
cmd /c $(CURRENT_DIRECTORY)\a.exe
the console worked fine and even received input
Here is a link to a similar problem:
How to compile/execute C++ code from within Notepad++

C++ code run in debug console rather in terminal in vs-code

I wanted to execute code in terminal not in debugger
After downloading all the c/c++ extension in vs-code.
code
#include<iostream>
using namespace std;
int main()
{ int UserInputOccur;
cout<<"helloworld";
cin>>UserInputOccur;
cout<<UserInputOccur;
return 0;
}
All the compilation and debugging done in debug console only till
( First user input i.e When first cin>>UserInputOccur; and then the code in terminated with helloworld1020=thread-exited,id="3",group-id="i1"
If you are using Linux you can write your code in a file, such as main.cpp.
Then you can open terminal -> go to the directory of the file -> run command g++ main.cpp -o main.
Now you can run your code on terminal with command ./main

Exe file not opening

I am trying to learn C++ now and created a Hello World program. When I compile it on Linux using g++ and it works perfectly fine. When I compile it on Windows using the Build tools, it still compiles the code into machine code, but I can't open the executable. I used the Microsoft build tools as a compiler. The code was:
#include <iostream>
using namespace std;
int main() {
cout << "Hello, World!";
}
The output should be: Hello, World!
**Question already answered:
The program closes because it is not run in cmd. To prevent the program from crashing add
```system("pause");```
at the end**
The executable is showing the correct output on the terminal, but that terminal closes that fast that you don't even realise it.
I'd advise you to open a command prompt, go to the directory where the executable is located and launch it over there. You'll see the desired output.
it possibility because
the app closes immediately after ouputing
add system("pause");
on the end
Its not that you can't open that exe file.
Once you click on that file, it opens up and does its work and closes.
To prevent your exe file from getting closed after doing its operation, you can add following line at the end of the main function :
getchar();
And now once you open your exe file, it wont close automatically, you will need to press "enter" to close it.
#include<iostream>
using namespace std;
int main(){
cout<<"hello world";
getchar();
}

Can't execute compiled C++ exe file

I am having trouble executing my C++ code. I have written a basic "Hello World" program, and compiled it using the g++ make command. Here is my code:
#include <iostream>
using namespace std;
int main() {
cout << "Hello World" << endl;
return 0;
}
I am on Windows 10, using Emacs for code editing, and CygWin for compilation. I saved this file as hello.cpp. I then navigated to the directory in CygWin. Then I did the command make hello. This created hello.exe. Then, I attempted to execute the file using ./hello.exe. I also tried ./hello which also didn't work. When I type one of these commands and hit Enter, it just on the next line, not doing anything. I can type in this blank line, but it won't do anything. Does anyone know a way to make my code execute properly. Thank you.
EDIT: I tried running this at cpp.sh, an online C++ compiler, and it worked fine.
Your program probably is working but the console window is closing before you can see anything.
Try adding an input at the end of the program so it will wait.
I.E.
int a;
cin >> a;
Your code is most likely executing, but not outputting anything. That's because it's failing. Try checking the return value after it has run with echo $?. If it's not 0 then it has crashed. Also run it in gdb and see if it fails. The reason why it's failing is most likely a windows/cygwin clash - it's not your code.