Find the largest number from a set of define and set a define from the answer

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Not sure you'll call this cleaner or simpler...:slight_smile: :scream: :innocent: but thought I would throw that out there for the sake of fun

C++ offers great evaluation (even at compile time) capabilities with constexpr and you can put that to work to your benefit by using templated recursive calls..

here is an example:

template <typename T> constexpr T maximum(T a) {return a ;}
template <typename T> constexpr T maximum(T a, T b) {return a > b ? a : b;}
template <typename T, typename... Targs> constexpr T maximum(T first, Targs... rest) {return maximum(first, maximum(rest...));}

#define numA 300
#define numB 600
#define numC 100
#define numD 200
#define numE 400
#define numF 500
#define numG 42

constexpr int numMax = maximum(numA, numB, numC, numD, numE, numF, numG);

void setup() {
  Serial.begin(115200); Serial.println();
  Serial.print(F("Max = ")); Serial.println(numMax);
}

void loop() {}

the great thing about this is — as demonstrated above — that you are no longer obliged to modify the macro if you have more or less than 4 values as the maximum() function takes a variable number of arguments ➜ you now can pass any number (1 or more) of constexpr arguments.

The other nice thing about it is the code size impact➜ NO code has been generated. It's evaluated at compile time for you by the compiler because everything is constexpr.

(of course I would discourage you to use the #define and go for constexpr as well for your numA, numB, ...) as strong typing always helps the compiler understand your intent.