it holiday season Koala decorate house cool light he own n light flash periodicallyafter take quick glance Koala realize light describe parameter a_i b_i light parameter a_i b_i toggle a_i second start b_ith second in word toggle moment b_i b_i a_i b_i 2 cdot a_i onYou know light initially correspond parameter a_i b_i Koala wonder maximum number light time so need find here graphic example