const int led1 = 13;
 const int led2 = 5;
 const int ldr1 = 0;
void setup() {
  pinMode(led1, OUTPUT);
  Serial.begin(9600);

}

void loop() {
  // put your main code here, to run repeatedly:
 int rate = analogRead(ldr1);
     rate = map(rate,0,1023,0,1);
     digitalWrite(led1,rate);
     Serial.print("the rate = ");
     Serial.println(rate);
     digitalWrite(led1, HIGH);
     delay(rate);
     digitalWrite(led1, LOW);
     delay(rate);

}