void setup() {
  Serial.begin(9600);
  pinMode(A0,INPUT);
  pinMode(11,OUTPUT);
}

void loop() {
  int data = analogRead(A0);
  Serial.print("Data = " + String(data));
  float resolution = 5.0 / 1023 ;
  float volt = data * resolution ;
  Serial.print("\t Volt = " + String(volt));
  int p = map(data , 0 , 1023 , 0 , 100);
  Serial.println("\t p = " + String(p));
  analogWrite(11 , p * 2.55);
  delay(250);
}