#define led1 7
#define led2 8
#define  interval1 1200
#define  interval2 3000

bool ledState1 = LOW;      
bool ledState2 = LOW;  

unsigned long previousMillis = 0; 
unsigned long previousMillis2 = 0; 

void setup() {
  pinMode(led2, OUTPUT);
  pinMode(led1, OUTPUT);
  Serial.begin(9600);
}


void loop() {
  
  unsigned long currentMillis = millis();

  if(currentMillis - previousMillis > interval1) {
    
    previousMillis = currentMillis;
    ledState1= !ledState1;

    
    digitalWrite(led1, ledState1);
  }
  if(currentMillis - previousMillis2 > interval2) {
    
    previousMillis2 = currentMillis;

    
    ledState2= !ledState2;
    
    digitalWrite(led2, ledState2);
  }
}