int botao;
int vn;

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(11, OUTPUT);
pinMode(10, OUTPUT);
pinMode(9, OUTPUT);
pinMode(4, INPUT_PULLUP);
pinMode(vn, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:

  vn = analogRead(A0);
  delay(100);
  vn = map(vn,0,1023,100,255);
  analogWrite(11,vn);
  analogWrite(11,vn);
  Serial.println(vn);
 
}