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int LED=A1;const int gas=0;int MQ2pin=A0;void setup(){ Serial.begin(9600); pinMode(9, OUTPUT);} void loop(){ float sensorvalue,MQ2pin; sensorvalue=analogRead(MQ2pin); if(sensorvalue>=400) { digitalWrite(LED,HIGH); digitalWrite(9,HIGH); Serial.print(sensorvalue); Serial.println(“/SMOKE DETECTED”); } else { digitalWrite(LED,LOW); digitalWrite(9,LOW); Serial.println(“Sensor value:”); Serial.println(sensorvalue); } delay(500);}float getsensorValue(int pin){ return(analogRead(pin));}