a=int(input()) a2=1998 monthdays=0 blackfriday=0 days2=3 days3=0 for i in range((a-1998+1)*12): days3+=1 if a2%4==0 and a2%100!=0: if i%12==0 or i%12==2 or i%12==4 or i%12==6 or i%12==7 or i%12==9 or i%12==11: monthdays=31 elif i%12==1: monthdays=29 else: monthdays=30 else: if a2%400==0 and a2%100==0: if i%12==0 or i%12==2 or i%12==4 or i%12==6 or i%12==7 or i%12==9 or i%12==11: monthdays=31 elif i%12==1: monthdays=29 else: monthdays=30 else: if i%12==0 or i%12==2 or i%12==4 or i%12==6 or i%12==7 or i%12==9 or i%12==11: monthdays=31 elif i%12==1: monthdays=28 else: monthdays=30 for j in range(1,monthdays+1): days2+=1 if days2==8: days2=1 if days2==5 and j==13: blackfriday+=1 if a2!=a: blackfriday=0 if days3%12==0: days3=0 a2+=1 print(blackfriday) /************************************************************** Problem: 1853 User: admin Language: Python Result: Accepted Time:515 ms Memory:34480 kb ****************************************************************/