int lm_35=A3;
int led=7;
void setup()
{
  pinMode(lm_35,INPUT);
  pinMode(led,OUTPUT);
  Serial.begin(9600);
}
void loop()
{
  int temp_adc;
  float temp;
  temp_adc=analogRead(lm_35);
  temp=(temp_adc*4.88)/10;
  temp=temp/10;
  Serial.println("Temperature =");
  Serial.println(temp);
  Serial.println("Degree Celsius");
  if(temp>30){
    digitalWrite(led,HIGH);
  }
  else{
    digitalWrite(led,LOW);
  }
delay(1000);
}