#include "nbdelay.h"

const int led_num = 4;
NBDELAY nbd1(100);
NBDELAY nbd2(200);
NBDELAY nbd3(300);
NBDELAY nbd4(400);
NBDELAY nbdto(1000);
NBDELAY *nbds[led_num] = {&nbd1,&nbd2,&nbd3,&nbd4};
int leds[led_num] = {2,3,4,5};

void setup() {
  for (int i=0;i<led_num;i++) {
    pinMode(leds[i],OUTPUT);
  }
}     

void loop() {
  for (int i=0;i<led_num;i++) {
    if (nbds[i]->nbd()) {
      digitalWrite(leds[i],!digitalRead(leds[i]));
    }
  }
  if (nbdto.nbd()) {
    nbds[random(0,led_num)]->set_delay(random(50,500));
  }
}