void setup() {
pinMode(A0, INPUT);
pinMode (5, OUTPUT);
pinMode (6, OUTPUT);
pinMode (10, OUTPUT);
pinMode (11, OUTPUT);
}

void loop() {

int s = analogRead(A0);
int v = map (s, 0, 1023, 0, 255);


if (s <= 256) {
analogWrite(5, v);
} else {
analogWrite(5, LOW);
}

if (s >= 256 && s < 512) {
analogWrite(6, v);
} else {
analogWrite(6, LOW);
}

if (s >= 512 && s < 768) {
analogWrite(10, v);
} else {
analogWrite(10, LOW);
}

if (s >= 768) {
analogWrite(11, v);
} else {
analogWrite(11, LOW);
}
}