// Arthur Renan Gutierrez Dias Pereira
int valor;
void setup()
{
 pinMode(8, OUTPUT);
 pinMode(6, OUTPUT);
 pinMode(4, OUTPUT);
 pinMode(2, OUTPUT);
}
void loop()
{
 valor = analogRead(A0);
 if(valor < 250){
 digitalWrite(6, LOW);
 digitalWrite(4, LOW);
 digitalWrite(2, LOW);
 digitalWrite(8, LOW);
 }
 if(valor > 250 and valor < 500){
 digitalWrite(6, HIGH);
 digitalWrite(4, LOW);
 digitalWrite(2, LOW);
 digitalWrite(8, LOW);
 }
 if(valor > 500 and valor < 750){
 digitalWrite(6, HIGH);
 digitalWrite(4, HIGH);
 digitalWrite(2, LOW);
 digitalWrite(8, LOW);
 }
 if(valor > 750){
 digitalWrite(6, HIGH);
 digitalWrite(4, HIGH);
 digitalWrite(2, HIGH);
 digitalWrite(8, HIGH);
 }
}