**Do not include a .cpp file inside another .cpp file [****Link**: 1-5 points]-
If you write #include "tools.cpp"

you are linking incorrectly. Use#include "tools.h"

and link correctly.

**Use parentheses in preprocessor definitions where appropriate [****Preprocessor**: 1 point] (optional)-
The preprocessor can define macros with parameters. For example, #define max(x,y) = (((x) > (y)) ? (x) : (y))

causes statementm = max(a+1,b);

to be replaced bym = (((a+1) > (b)) ? (a+1) : (b));

Notice that each parameter in the definition of max is enclosed in parentheses, as it should be, and the entire right-hand side is parenthesized. Ensure that substitutions cannot cause precedence rules to yield a reparse. For example#define successor(x) x+1

does not parenthesize. It causesm = 2*successor(n-i);

to be replaced bym = 2*n-i+1;

which is not what was intended. A correct definition of successor is#define successor(x) ((x)+1)