Advent-of-Code-2023/day12/notes.org

Notes

• i guess let's generate all possible? and short circuit when they are not matching mask
• wrong answer on input
  • huh, nope this looks good:
  • let's check this : for line ??????#???????? blocks [7 2] matches 21
  • or this for line ?????.??#????? blocks [3 3 2 1] matches 3
  • this for line ??..??#?????#?##? blocks [1 1 1 1 4] matches 15
  • for line ?#??#??#???.??.??.? blocks [1 2 3 1 1 1] matches 20
  • for line ???????#??.????####? blocks [1 1 1 1 1 6] matches 58
• well, maybe overnight will calculate.
  • for example

i guess let's generate all possible? and short circuit when they are not matching mask

how do i generate all possible?

i take length of the mask, that's max size then for each step, either put . or put n # from the input.

add to current string, and do 2 recursive calls, one with diminished 'queue', one with same

wrong answer on input

it's too high

and log shows:

2023/12/12 15:07:52 for line ???#?.?#?#.?#???#..? blocks [4 4 5 1] matches 2

and it should be 0

huh, nope this looks good:

testMask := "???#?.?#?#.?#???#..?" testBlocks := []int{4,4,5,1} testVariants := generatePermutations("", len(testMask), testBlocks, 14, testMask) fmt.Printf("for mask %s and blocks %+v\n", testMask, testBlocks) fmt.Println(testVariants)

for mask ???#?.?#?#.?#???#..? and blocks [4 4 5 1] [####..####..#####..# .####.####..#####..#]

let's check this : for line ??????#???????? blocks [7 2] matches 21

or this for line ?????.??#????? blocks [3 3 2 1] matches 3

looks ok

this for line ??..??#?????#?##? blocks [1 1 1 1 4] matches 15

looks good

for line ?#??#??#???.??.??.? blocks [1 2 3 1 1 1] matches 20

seems ok

for line ???????#??.????####? blocks [1 1 1 1 1 6] matches 58

bingo?

for mask ???????#??.????####? and blocks [1 1 1 1 1 6] #.#.#..#.#.######… #.#.#..#.#..######.. #.#.#..#.#…######. #.#.#..#.#….###### #.#.#..#…#.######. #.#.#..#…#..###### #.#.#..#….#.###### #.#..#.#.#.######… #.#..#.#.#..######.. #.#..#.#.#…######. #.#..#.#.#….###### #.#..#.#…#.######. #.#..#.#…#..###### #.#..#.#….#.###### #.#….#.#.#.######. #.#….#.#.#..###### #.#….#.#..#.###### #..#.#.#.#.######… #..#.#.#.#..######.. #..#.#.#.#…######. #..#.#.#.#….###### #..#.#.#…#.######. #..#.#.#…#..###### #..#.#.#….#.###### #..#…#.#.#.######. #..#…#.#.#..###### #..#…#.#..#.###### #…#..#.#.#.######. #…#..#.#.#..###### #…#..#.#..#.###### #….#.#.#.#.######. #….#.#.#.#..###### #….#.#.#..#.###### .#.#.#.#.#.######… .#.#.#.#.#..######.. .#.#.#.#.#…######. .#.#.#.#.#….###### .#.#.#.#…#.######. .#.#.#.#…#..###### .#.#.#.#….#.###### .#.#…#.#.#.######. .#.#…#.#.#..###### .#.#…#.#..#.###### .#..#..#.#.#.######. .#..#..#.#.#..###### .#..#..#.#..#.###### .#…#.#.#.#.######. .#…#.#.#.#..###### .#…#.#.#..#.###### ..#.#..#.#.#.######. ..#.#..#.#.#..###### ..#.#..#.#..#.###### ..#..#.#.#.#.######. ..#..#.#.#.#..###### ..#..#.#.#..#.###### …#.#.#.#.#.######. …#.#.#.#.#..###### …#.#.#.#..#.######

well, maybe overnight will calculate.

but i guess i needed to check whether blocks are 'always' taking full width then i'll only need to calculate once, and then multiply

for example

2023/12/12 20:40:41 699 : for line ??#?????#???.? ???#?????#???.????#?????#???.????#?????#???.????#?????#???.? blocks [3 1 2 1 3 1 2 1 3 1 2 1 3 1 2 1 3 1 2 1] matches 38294856

??#?? ???#?? ?.? 3,1,2,1 - 10+3 = 13

lowest s ###.#.##.#….. - plenty of space for additional