int sensorPin = 7; /*  select the input pin for LDR */
int sensorValue = 0; /*  variable to store the value coming from the sensor */
int LEDPin = 3;

void setup(void) 
{ 
  pinMode(sensorPin, INPUT);
  pinMode(LEDPin, OUTPUT);
 
} 


void loop(void) 
{ 

sensorValue = analogRead(sensorPin); //Read data from analog pin and store it to value variable

 // Mapping values of photoresistor to light of LED
  sensorValue = map(sensorValue,200,400,0,255);
  analogWrite(LEDPin, sensorValue);
  delay(1000);
}