fn day_of_programmer(year: i32) -> String {
    let mut days_of_month: [usize; 12] = [31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
    days_of_month[1] = match year {
        1700..=1917 => if year % 4 == 0 { 29 } else { 28 }, // julian
        1919..=2700 => if year % 400 == 0 || (year % 4 == 0 && year % 100 != 0) { 29 } else { 28 }, // gregorian
        1918 => 15, // transition year
        _ => panic!("time traveler error")
    };
    let mut days = 256usize;
    let mut i = 0usize;
    while days > days_of_month[i] {
        days -= days_of_month[i];
        i += 1;
    }
    format!("{:02}.{:02}.{year}", days, i+1)
}