I have installed Fedora 11 and Ubuntu 9.10 and have instaled development packages(gcc,gc++,..) in both i am able to compile and execute c programs but when it comes to c++ i get an error...
i ve tried using cc & gcc..
how can i over come this??

Hi

When compiling C++, use the command "g++" instead of "gcc".

1 members found this post helpful.

tryed c++ and g++ too still getting same errors..
i have also set executing permissions for the files..

Then post the error messages?

[temp@satheesh Documents]$ vi sam.cpp
#include<iostream>
main()
{
cout<<"Welcome\n";
}
[temp@satheesh Documents]$ cc sam.cpp
sam.cpp: In function ‘int main()’:
sam.cpp:4: error: ‘cout’ was not declared in this scope

[temp@satheesh Documents]$ vi sam.java
public class HelloWorld {
public static void main(String[] args) {
System.out.println("Hello World!");
}
}
[temp@satheesh Documents]$ ll
total 8
-rwxr-xr-x. 1 temp temp 49 2009-11-18 14:33 sam.cpp
-rwxr-xr-x. 1 temp temp 118 2009-11-18 14:46 sam.java
[temp@satheesh Documents]$ java sam.java
Exception in thread "main" java.lang.NoClassDefFoundError: sam/java
Caused by: java.lang.ClassNotFoundException: sam.java
at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:323)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
at java.lang.ClassLoader.loadClass(ClassLoader.java:268)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:336)
Could not find the main class: sam.java. Program will exit.
[temp@satheesh Documents]$

Try

g++ sam.cpp

instead of

cc sam.cpp

You also need the line

using namespace std;

before the main function.

1 members found this post helpful.

why should one use using namespace std;
i am able to compile it after including it..
how about java??
what shall i do??

Hi

Well cout is part of the std library of C++. And everything in it is in the std namespace. If you don't have "using namespace std" you can use std::cout instead of cout.

As for Java, you have to compile the Javaprogram using javac. And then you need Java sdk or jdk, not just the jre. The javac compiler will make a .class file you can run.

1 members found this post helpful.

First, your java program will not compile as is. The line that says must match the file name - you either need to change the name to HelloWorld.java OR change the line to say .

Then you need to build the java file (assuming you have a Java Development Kit installed) using and then run using.