// what pin what ah
const int input = A7; 
//DO NOT CONNECT OUT TO D2, it no have ~
const int output = 3; 

//define value
int light = 0;        

void setup() {
// put your setup code here, to run once:
}

void loop() {
  //get and devide 
  light = analogRead(input) / 4;
  //send out
  analogWrite(output, light);
}

#include <Servo.h>

Servo myservo;

int angle = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  myservo.attach(9);
}

void loop() {
  // put your main code here, to run repeatedly:
  int value0 = analogRead(A0);
  int value1 = analogRead(A1);

  Serial.print(value0);
  Serial.print(",");
  Serial.print(value1);
  Serial.print(",");
  Serial.println(angle);
  int difference = value0 - value1;
  const int range = 100;
  if (difference > range)
  {
    if (angle < 180 or angle > 0)
    {
      myservo.write(angle++);
      delay(10);
    }
  }
  else if (difference < -range)
  {
    if (angle < 180 or angle > 0)
    {
      myservo.write(angle--);
      delay(10);
    }
  }
  else {}
  /*
  for (angle = 0; angle <= 180; angle+= 1)
  {
    myservo.write(angle);
    delay(15);
  }
  for (angle = 180; angle >= 0; angle+= -1)
  {
    myservo.write(angle);
    delay(15);
  }
  */
}