void setup() {
  int a,b,c;
  unsigned int d;
  float e;
  a=-20;
  b=20.5;
  e=20.5;

  Serial.begin(9600);// put your setup code here, to run once:
  Serial.println(a);
  Serial.println(b);
  Serial.println(e);
  d=-20;
  Serial.println(d);
  d=65535;
  Serial.println(d);
  d=d+1;
  Serial.println(d);
}

void loop() {

}