day 12 cleanup

main
magical 2023-12-12 09:40:29 +00:00
parent 99405e2ad0
commit c55423d6f3
1 changed files with 26 additions and 34 deletions

View File

@ -2,27 +2,25 @@
source ../prelude.tcl
set input stdin
array set ::m {}
proc memo {row nums i left} {
proc count-memo {row nums i left} {
global memo
if {$i == 0} {
array unset memo
}
set key "$i,$left,[llength $nums]"
if {[info exists ::m($key)]} {
if {[info exists memo($key)]} {
#puts "$key exists"
#puts [array get ::m]
return $::m($key)
return $memo($key)
}
set n [count $row $nums $i $left]
set ::m($key) $n
set memo($key) $n
return $n
}
proc count {row nums i left} {
#puts [list count $row $nums $i $left]
if {$i >= [string length $row]} {
if {[llength $nums] > 0} {
return 0
}
return [expr {$left > 1 ? 0 : 1}]
return [expr {($left > 1 || [llength $nums] > 0) ? 0 : 1}]
}
if {[llength $nums] <= 0 && $left <= 0} {
return [expr {[string first "#" $row $i] >= 0 ? 0 : 1}]
@ -31,70 +29,64 @@ proc count {row nums i left} {
incr i
if {$c eq "."} {
if {$left > 1} {
# contradiction: expecting a "#"
return 0
} elseif {$left == 1} {
# left counts the number of "#" left in the current group,
# plus the "." at the end. if left==1 then we've seen all
# the "#" and now we need to see a "."
set left 0
} else {
# nothing
}
return [memo $row $nums $i $left]
return [count-memo $row $nums $i $left]
}
if {$c eq "#"} {
if {$left > 1} {
incr left -1
} elseif {$left == 1} {
# contradiction: expecting a "."
return 0
} else {
set nums [lassign $nums left] ;# shift nums
}
return [memo $row $nums $i $left]
return [count-memo $row $nums $i $left]
}
if {$c eq "?"} {
if {$left > 1} {
# must be "#"
incr left -1
#set row [string replace $row $i-1 $i-1 "#"]
return [memo $row $nums $i $left]
return [count-memo $row $nums $i $left]
} elseif {$left == 1} {
# must be "."
set left 0
#set row [string replace $row $i-1 $i-1 "."]
return [memo $row $nums $i $left]
return [count-memo $row $nums $i $left]
} else {
# bifurcate
# "."
#set row [string replace $row $i-1 $i-1 "."]
set a [memo $row $nums $i $left] ;# "."
set a [count-memo $row $nums $i $left]
set nums [lassign $nums left]
# "#"
#set row [string replace $row $i-1 $i-1 "#"]
set b [memo $row $nums $i $left] ;# "#"
set b [count-memo $row $nums $i $left]
return [expr {$a + $b}]
}
}
error "invalid character '$c' at position $i"
}
proc match {row nums} {
#puts -nonewline " $row -> "
set row [string map {. " "} $row]
#puts " $row"
foreach group $row n $nums {
if {[string length $group] != $n} {
return 0
}
}
return 1
}
set part1 0
set part2 0
while {[gets $input line] >= 0} {
set n 0
lassign $line row nums
set row "$row?$row?$row?$row?$row"
set row [string trim $row "."]
#set row [string trim $row "."]
set nums [split $nums ","]
set nums [concat $nums $nums $nums $nums $nums]
array unset ::m
set n [memo $row $nums 0 0]
set n [count-memo $row $nums 0 0]
puts "$n | $row $nums"
incr part2 $n
}