int plavaLED = PB5;
int zelenaLED = PB3;
int crvenaLED = PB4;
void setup() 
{
  pinMode(plavaLED, OUTPUT);
  pinMode(zelenaLED, OUTPUT);
  pinMode(crvenaLED, OUTPUT);
}
void loop()
{
    digitalWrite(plavaLED, HIGH);
    digitalWrite(zelenaLED, LOW);
    digitalWrite(crvenaLED, LOW);
    delay(1000);
    digitalWrite(plavaLED, LOW);
    digitalWrite(zelenaLED, HIGH);
    digitalWrite(crvenaLED, LOW);
    delay(1000);
    digitalWrite(plavaLED, LOW);
    digitalWrite(zelenaLED, LOW);
    digitalWrite(crvenaLED, HIGH);
    delay(1000);
}