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It would be easier to help you if you explain a little more about what you're trying to do.

If you want to compile a small, single file, C++ program in a file called test.cpp, you can use the Terminal command g++ like so:

g++ test.cpp -o test

Then you can execute it like so:

./test
 
You can use CPP Edit to compile simple, one-file C++ programs, but if you are going to be working on big projects, either use Xcode or the Terminal to compile.
 
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