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NOOBIE C++ Question

Code:

#include <iostream>





int main()

{



        int number1;

            int number2;

        int sum;

        

        std::cout << "Enter first integer: ";

        std::cin >> number1;

                

        std::cout << "Enter second integer: ";

        std::cin >> number2;



        sum = number1 + number2;



        std::cout << "Sum is " << sum << std::end1;

        

        return 0;



}

im going by the book and im having some issues here it wont compile successfully the error is:

Code:

[Donald@localhost ~]$ cd Desktop/C++

[Donald@localhost C++]$ make addition

make: *** No rule to make target `addition'.  Stop.

Do you even have a Makefile created in ~/C++ ?

no it did not create a executable

A makefile is a kind of a template. It tells gcc how to build a application. It tells gcc what kind of command line options to use, what kind of objects to compile, and other things such as where to look for headers files and shared libraries. If you don't want to bother to learn 'make' you can do as many do, install an IDE such as Eclipse. That is what I did.

a make file? i didnt use it for my previous program to compile why do i need it now? they are just console programs

You don't really have to have one (it makes it easier if you have a lot of objects that are being compiled and linked into the final program) if you are just compiling one source file, you can use g++ on the comand line if you use the right options.

By the way, I compiled your program and it had an error in it. I'll let you figure out what it is when you get it to compile. That the 'fun' part of learning to program.

So, why are you running make?

Quote:

Originally Posted by alan99 (Post 4087461)

By the way, I compiled your program and it had an error in it. I'll let you figure out what it is when you get it to compile. That the 'fun' part of learning to program.

yea ifound it to endl it was a 1 instead of the L but still did not fix my problem i think something is wrong with my compiler

When you run "make", it tries to read a file (called a makefile, usually named "Makefile"). This file contains information on how to compile a program.

Since you have no Makefile, make does not know how to compile the program. You could either do it manually, with g++, or you can write a Makefile (there's also cmake, autotools, and several other pieces of software I don't know how to use.)

"g++" is the C++ compiler. You can invoke it to compile this program with:

Code:

g++ addition.cpp -o addition

This will produce this program as an executable.

A makefile contains targets. For example, to compile a program named "main" from the file "main.cpp", you could add as a rule (make is picky on tabs vs. spaces):

Code:

main: main.cpp

<tab>g++ main.cpp -o main

Most makefiles start (i.e. it must be first) with the target "all", as a convention:

Code:

all: main

and include a "clean" target:

Code:

clean:

<tab>rm -f main

You could compile by hand, with g++, or you could read up on Makefiles. I hope this has enough information for you to write a makefile for this program.

And, as alan99 said, there is an error in the program. You'll figure it out.

Post any issues you have if you try to write a Makefile for this project.

EDIT: you found the error with "end1" vs "endl"

Quote:

Originally Posted by crosstalk (Post 4087506)

Code:

g++ addition.cpp -o addition

Code:

main: main.cpp

<tab>g++ main.cpp -o main

Most makefiles start (i.e. it must be first) with the target "all", as a convention:

Code:

all: main

and include a "clean" target:

Code:

clean:

<tab>rm -f main

Thank you so much for your time for writing all this up!!! So your saying if i want to by-pass these problems i can just use

Code:

g++ addition.cpp -o addition

while my programs are quite simple. and when i get into more complex programs then i might have to use a makefile.

If you need to compile the C++ file, just use g++ if it's one file, like so:

Code:

$ g++ -Wall -Wextra -o addition addition.cpp

Quote:

Originally Posted by donaldfarkas (Post 4087566)

So your saying if i want to by-pass these problems i can just use

Code:

g++ addition.cpp -o addition

while my programs are quite simple. and when i get into more complex programs then i might have to use a makefile.

That is correct, although you (almost) never have to use a makefile (make is just used for convenience.) Just remember -- many programs have hundreds of source files, and running "g++" (and any other pieces of software, such as a linker) on all of them would be quite tiresome without make.

Glad I could help. Good luck learning C++.

Also, make compiles only the files that changed, saving time for big multi-file projects.

[Donald@localhost ~]$ cd Desktop/C++
[Donald@localhost C++]$ ls
addition.cpp printingLineofText
[Donald@localhost C++]$ g++ addition.cpp -o addition
g++: addition.cpp: No such file or directory
g++: no input files
[Donald@localhost C++]$ ^C
[Donald@localhost C++]$

so above paste shows that i have navigated to the right directory and showing that the file is thereand then i try to compile and shows no such file