int temp = 20;
int ntc = A0;
int knap = 4;
int valuentc;
int valueknap;
int diode = 5;
const float BETA = 3950;


void setup() {
  pinMode(knap, INPUT_PULLUP);
  pinMode(ntc, INPUT);
  pinMode(diode, OUTPUT);

  Serial.begin(1000);
}

void loop() {
 
valueknap = analogRead(knap);
valuentc = analogRead(ntc);
float celsius = 1 / (log(1 / (1023. / valuentc - 1)) / BETA + 1.0 / 298.15) - 273.15;
Serial.print("Grader");
Serial.print(" ");
Serial.print(celsius);
Serial.print("     ");
Serial.print("Knapværdi");
Serial.print(" ");
Serial.println(digitalRead(knap));

if(digitalRead(knap)==0){
if (celsius > temp){
  digitalWrite(diode, HIGH);
}else{
  digitalWrite(diode, LOW);
}
}else{
  if(celsius < temp){
    digitalWrite(diode, HIGH);
  }else{
    digitalWrite(diode, LOW);
  }

}
}