int a = 2;
int b = 3;
float c = 4.5;
float d = 5.6;


void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  float res = a * b;
  float res2 = c / d;
  Serial.println(res - res2);
}

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

}