import sys def is_leap_year(year): return (year % 400 == 0) or (year % 4 == 0 and year % 100 != 0) def day_of_month(year,month,day): day_in_month = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] if is_leap_year(year): day_in_month[1] = 29 return sum(day_in_month[:mont...