Convert C/C++ program to Preprocessor code

We use g++ compiler to turn provided Cpp code into preprocessor code. To see the preprocessor code generated by the CPP compiler, we can use the “-E” option on the command line:
Preprocessor include all the # directives in the code. and also expands MACRO function.

g++ -E filename.cpp




// MACRO named MAX initialism to 10
#define MAX 10
int main()
    int a = MAX, b = MAX;
    // Add two values.
    int c = a + b;
    return 0;


Running the command:

g++ -E

Output :

int main()

    int a = 10, b = 10;

    // Add two values.
    int c = a + b;

    return 0;

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