Snippet to receive digital value from sensor and print

print_serial_sensor.arduino

const int ProxSensor = 2;

void setup() {
  // put your setup code here, to run once:
  pinMode(13, OUTPUT);
  pinMode(ProxSensor,INPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  int sensorValue = digitalRead(ProxSensor);
  Serial.println(sensorValue);
  delay(100);
}