int ledverde = 23;
int ledamarelo = 22;
int ledvermelho = 21;
int ldr = 4;
int led4 = 19;

void setup() {
  Serial.begin(9600);
pinMode(ledverde, OUTPUT);
pinMode(ledamarelo, OUTPUT);
pinMode(ledvermelho, OUTPUT);
pinMode(led4, OUTPUT);
pinMode(ldr, INPUT);
}

void loop() {
digitalWrite(ledverde, HIGH);
digitalWrite(ledamarelo, LOW);
digitalWrite(ledvermelho, LOW);
delay(5000);
digitalWrite(ledverde, LOW);
digitalWrite(ledamarelo, HIGH);
digitalWrite(ledvermelho, LOW);
delay(2000);
digitalWrite(ledverde, LOW);
digitalWrite(ledamarelo, LOW);
digitalWrite(ledvermelho, HIGH);
delay(4000);
int valorldr = analogRead(ldr);
Serial.println(valorldr);
if(valorldr < 1500){
  digitalWrite(led4, HIGH);
}else{
  digitalWrite(led4, LOW);
}
delay(2000);
}