Light Magic: Using LM393 and Arduino UNO

1void setup() {
2  pinMode(8,INPUT);
3  pinMode(9,OUTPUT);
4  Serial.begin(9600);  //initialise serial monitor
5
6}
7
8void loop() {
9  int temp=digitalRead(8);      //assign value of LDR sensor to a temporary variable
10  Serial.println("Intensity=");  //print on serial monitor using ""
11  Serial.println(temp);         //display  output on serial monitor
12  delay(300);
13  if(temp==HIGH)               //HIGH  means,light got blocked
14  digitalWrite(9,HIGH);        //if light is not present,LED  on
15  else
16  digitalWrite(9,LOW);         //if light is present,LED off
17}