int led1 = 12;
int led2 = 11;
int p_b = 5;
int flag = 0;



void setup() {
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
  pinMode(p_b, INPUT);
  // put your setup code here, to run once:

}

void loop() {
   int  click=digitalRead(p_b);
   if(click==1 and flag ==0)
  {
    digitalWrite(led1, HIGH);
    delay(1000);
    digitalWrite(led2, LOW);
    delay(1000);
    flag = 1;

  }
   else if(click==1 and flag == 1)
  {
    digitalWrite(led1,LOW);
    delay(1000);
    digitalWrite(led2, HIGH);
    delay(1000);
    flag=2;
    
  }
  else if(click==1 and flag ==2)
  {
    digitalWrite(led1, HIGH);
    delay(1000);
    digitalWrite(led2, HIGH);
    delay(1000);
    flag=3;

  }
  else if (click==1 and flag==3)
  {
    digitalWrite(led1, LOW);
    delay(1000);
    digitalWrite(led2, LOW);
    delay(1000);
    flag=0;
  }


  // put your main code here, to run repeatedly:

}