/*
 The MQ-3 sensor is used to detect alcohol. It an be programed by arduino.
 Here, we build a program to identify ethanol vapor. 

In the MQ-3 sensor, there are four pins.
1. VCC
2. GND
3. DO
4. AO

VCC, GND, AO pins are connceted to the arduino. 
 */

int sensorPin = A0;    // select the input pin for the MQ-3 sensor
int sensorValue = 0;  // variable to store the value coming from the sensor

void setup() {
  Serial.begin(9600);
}

void loop() {
  // read the value from the sensor:
  sensorValue = analogRead(sensorPin);

Serial.print("MQ3 sensor value: ");
 Serial.println(sensorValue);
 delay(1000);
 
}