int lm35=A1;
int ledgreen=3;
int ledred=2;
int ledyellow=4;
void setup()
{
  pinMode(lm35, INPUT);
  pinMode(ledred, OUTPUT);
  pinMode(ledgreen, OUTPUT);
 pinMode(ledyellow, OUTPUT);
  Serial.begin(9600);
}
void loop()
{
  int temp_adc_val;
  float temp_val;
  temp_adc_val=analogRead(lm35);
  temp_val=(temp_adc_val*4.88);
  temp_val=(temp_val/10);
  Serial.print("temp : ");
  Serial.print(temp_val);
  Serial.println("celsius");
  delay(200);
  if(temp_val>400)
  {
    digitalWrite(ledgreen, HIGH);
     digitalWrite(ledred,LOW);
      digitalWrite(ledyellow,LOW);
    Serial.println("temp is high");
    delay(200);
  }
  else if((temp_val>120)&&(temp_val<400))
  {
    digitalWrite(ledred,HIGH);
     digitalWrite(ledgreen,LOW);
      digitalWrite(ledyellow,LOW);
    Serial.println("temp is normal");
    delay(200);
  }
 else if(temp_val<120)
  {
    digitalWrite(ledyellow, HIGH);
     digitalWrite(ledred,LOW);
      digitalWrite(ledgreen,LOW);
    Serial.println("temp is low");
    delay(200);
  }
  }