# Advent calendar 2019

## 25 December

It's nearly Christmas and something terrible has happened: while out on a test flight, Santa's sled was damaged and Santa, Rudolph and Blitzen fell to the ground over the Advent Isles.
You need to find Santa and his reindeer before Christmas is ruined for everyone.

You have gathered one inhabitant of the four largest Advent Isles—Rum, Land, Moon and County—and they are going to give you a series of clues about where Santa and his reindeer landed.
However, one or more of the islanders you have gathered may have been involved in damaging Santa's sled and causing it to crash: any islander involved in this will lie to you to attempt to stop
you from finding Santa and his reindeer.
Once you are ready to search for Santa, Rudolph and Blitzen, you can find the map by following this link.

Each of the clues will be about Santa's, Rudolph's or Blitzen's positions in Advent Standard Coordinates (ASC): ASC are given by six two-digit numbers with dots inbetween, for example

**12.52.12.13.84.55**. For this example coordinate, the islanders will refer to (the first)**12**as the first coordinate,**52**as the second coordinate, (the second)**12**as the third coordinate,**13**as the fourth coordinate,**84**as the fifth coordinate, and**55**as the sixth coordinate.Here are the clues:

3

Rum says: "The product of all the digits in Blitzen's six coords is **432**."

21

Moon says: "Blitzen's fifth coord is **23**."

9

Moon says: "Blitzen's third coord is **23**."

1

Land says: "Santa's third coord ends in **3**,

**0**or

**1**."

2

Land says: "Santa's third coord ends in **2**,

**0**or

**3**."

4

Rum says: "Santa's second coord ends in **3**,

**4**or

**1**."

12

Rum says: "Rudolph's second and sixth coords are both **64**."

10

Rum says: "All six of Rudolph's coords are factors of **256**."

18

Moon says: "Santa's fourth and fifth coords are both **79**."

24

County says: "Santa's third coord ends in **3**,

**2**or

**1**."

22

Land says: "Santa's sixth coord is not **43**."

7

Rum says: "Santa's sixth coord is **43**."

23

County says: "One of the digits of Santa's third coord is **7**."

25

✔14

Land says: "Santa's third coord is **12**."

5

Rum says: "Santa's first coord is **36**."

15

Rum says: "Blitzen's first coord is **23**."

17

Rum says: "The first digit of Santa's third coord is **1**."

8

County says: "Santa's third coord shares a factor (≠1) with **270**."

6

County says: "Santa's second coord is **21**."

16

Land says: "Blitzen's second coord is **21**."

20

Moon says: "All six of Rudolph's coords are multiples of **8**."

11

Moon says: "The sum of Rudolph's six coords is **192**."

13

Moon says: "Santa's second coord is **21**or

**11**."

19

Moon says: "Blitzen's fourth and sixth coords are both **11**."

To find a point's ASC coordinates, split a map of the islands into a 9×9 grid, then number the rows and columns 1 to 9: the first two digits of ASC give the vertical then horizontal position of a square in this grid.
The next two digits then give a smaller square when this square is then itself split into a 9×9 grid, and so on. An example is show below.

You can view the map here.