the academic year begin lesson olympiad occupy free time it surprise today Olga fall asleep Literature she dream stair the stair consist n step the step number mean low step number 1 high step number n Above pointer direction Olga step as soon Olga go step direction pointer step leave change it mean direction change direction direction upolga move step direction show pointer step if Olga move stair fall wake move stair move step move mean nth step in second Olga move step accord direction pointer locate step Olga begin second for step find duration dream Olga step begin dreamOlgas fall take second step go wake second