adventofcode2023/day13/sol.tcl

81 lines
1.9 KiB
Tcl
Executable File

#!/usr/bin/env tclsh
source ../prelude.tcl
set input stdin
set patterns [splitstr [trim [read $input]] "\n\n"]
set patterns [lmap p $patterns {split $p "\n"}]
puts "$patterns"
proc reflect pattern {
set total 0
foreach pat [list $pattern [transpose $pattern]] factor {100 1} {
#puts "reflect $pat"
for {set i 1} {$i < [llen $pat]} {incr i} {
set ok 1
for {set j 0} {$i + $j < [llen $pat] && $i-$j-1 >= 0} {incr j} {
if {[lindex $pat $i+$j] ne [lindex $pat [expr {$i-$j-1}]]} {
set ok 0
break
}
}
if {$ok} {
#puts "$i $factor"
incr total [expr {$i * $factor}]
}
}
}
return $total
}
proc fix pattern {
set total 0
foreach pat [list $pattern [transpose $pattern]] factor {100 1} {
#puts "reflect $pat"
array unset smudges
for {set i 1} {$i < [llen $pat]} {incr i} {
set diff 0
for {set j 0} {$i + $j < [llen $pat] && $i-$j-1 >= 0} {incr j} {
incr diff [distance [lindex $pat $i+$j] [lindex $pat [expr {$i-$j-1}]]]
if {$diff > 1} break
}
if {$diff == 1} {
#puts "$i $factor"
incr total [expr {$i * $factor}]
}
}
}
return $total
}
proc distance {a b} {
set d 0
foreach x [split $a ""] y [split $b ""] {
incr d [expr {$x ne $y}]
}
return $d
}
proc column {lst i} {
set c {}
foreach row $lst {
lappend c [string index $row $i]
}
return [join $c ""]
}
proc transpose pat {
set C [slen [lindex $pat 0]]
set out {}
for {set i 0} {$i < $C} {incr i} {
lappend out [column $pat $i]
}
return $out
}
foreach pat $patterns {
puts "[fix $pat] <| $pat"
}
puts [ladd [lmap pat $patterns {reflect $pat}]]
puts [ladd [lmap pat $patterns {fix $pat}]]