/*
  Blink

  Turns an LED on for one second, then off for one second, repeatedly.

  Most Arduinos have an on-board LED you can control. On the UNO, MEGA and ZERO
  it is attached to digital pin 13, on MKR1000 on pin 6. LED_BUILTIN is set to
  the correct LED pin independent of which board is used.
  If you want to know what pin the on-board LED is connected to on your Arduino
  model, check the Technical Specs of your board at:
  https://www.arduino.cc/en/Main/Products

  modified 8 May 2014
  by Scott Fitzgerald
  modified 2 Sep 2016
  by Arturo Guadalupi
  modified 8 Sep 2016
  by Colby Newman

  This example code is in the public domain.

  http://www.arduino.cc/en/Tutorial/Blink
*/

// the setup function runs once when you press reset or power the board
const int BUTTON[4]={12,10,8,6};
const int LED[4]={13,11,9,7};

int BUTTONstate = LOW;
void setup()
{
  for(int i=0;i<4;i++){
    pinMode(BUTTON[i], INPUT);
    pinMode(LED[i], OUTPUT);
  }
}
void blink(int i){
   BUTTONstate = digitalRead(BUTTON[i]);
  if (BUTTONstate == HIGH)
  {
   for(int j=0;j<i+1;j++){
     digitalWrite(LED[i], HIGH);   // turn the LED on (HIGH is the voltage level)
      delay(1000/(i+1));                       // wait for a second
      digitalWrite(LED[i], LOW);    // turn the LED off by making the voltage LOW
      delay(1000/(i+1));
   }
  } 
  else{
    digitalWrite(LED[i], LOW);
  }
}
void loop()
{
  blink(0);
  blink(1);
  blink(2);
  blink(3);
  
}