#include <limits.h>

void setup() {
  // put your setup code here, to run once:

  Serial.begin(115200);

  unsigned long t1  = ULONG_MAX - 100UL;
  unsigned long t2  = ULONG_MAX - 10UL;

      if ((signed long)(t1 - t2) > 0) {
        Serial.println("positive");
      }else{
        Serial.println("negative");
      }
}

void loop() {
  // put your main code here, to run repeatedly:

}




// prints "negative"