2 files changed, 114 insertions, 0 deletions
diff --git a/10/1.tcl b/10/1.tcl
new file mode 100644
index 0000000..08222d9
--- /dev/null
+++ b/10/1.tcl
@@ -0,0 +1,61 @@
+set fp [open "input" r]
+set line {}
+while {[gets $fp line] >= 0} {
+    lappend lines $line
+}
+close $fp
+
+set height [llength $lines]
+set width [string length [lindex $lines 0]]
+
+proc out_of_range {x y} {
+    global height width
+    if {$x < 0 || $x >= $width} {
+        return 1
+    }
+    if {$y < 0 || $y >= $height} {
+        return 1
+    }
+    return 0
+}
+
+proc char_at {x y} {
+    global lines
+    if {[out_of_range $x $y]} {
+        return -1
+    }
+    return [string index [lindex $lines $y] $x]
+}
+
+set path_cache {}
+
+proc find_path {x y expect} {
+    global path_cache
+    if {[out_of_range $x $y]} {
+        return 0
+    }
+    if {$expect != [char_at $x $y]} {
+        return 0
+    }
+    if {$expect == 9} {
+        dict set path_cache "$x,$y" {}
+        return 1
+    }
+    set next [expr {$expect + 1}]
+    set ret [expr {
+        [find_path [expr {$x + 1}] $y $next]
+        + [find_path [expr {$x - 1}] $y $next]
+        + [find_path $x [expr {$y + 1}] $next]
+        + [find_path $x [expr {$y - 1}] $next]
+    }]
+}
+
+set sum 0
+for {set x 0} {$x < $width} {incr x} {
+    for {set y 0} {$y < $height} {incr y} {
+        set path_cache {}
+        find_path $x $y 0
+        incr sum [dict size $path_cache]
+    }
+}
+puts $sum
diff --git a/10/input b/10/input
new file mode 100644
index 0000000..d454397
--- /dev/null
+++ b/10/input
@@ -0,0 +1,53 @@
+65456780121098450187634569763232345103213014321223456
+56565097632787543296323478890141234234102125630310767
+67874198545601612345610165765650105145693496543407898
+32923238723432709654326543034789076008786587854343210
+41010129610549878723017832129878989019895674963210349
+03498034534698965014898901038965432123107895674310478
+12567012345787854198743230123453219654256456789321565
+01698107659834723085650134562104508723340349876459874
+98787238543225610176590121875698698812451210145960123
+07456549850110765203485430984788767904322109236871234
+12349654763234894312176534983109456765012218347120105
+45898763120125234523054325672112309876544367898034876
+36765812034576127654369010766043218987432458765565989
+29876903107681038923478001897652345898901089014877856
+10945789218996987610569123078901236754321198123966987
+89032654309345678510787430121230109865120567001855496
+70121023498210709425698945230381210778034056532743345
+63210110567601812334321876545496321689765123443412210
+54216787014503956745430965496587434509894329856301101
+09105496923212345866787634987676543213456018763456932
+18012387836781078975898523432345232122347890345367873
+27601078745896769784309410541230143021038901276216784
+34587669654305854693210305670321056523427987689105698
+03490548741214903543211234781987897012310094576543567
+12321239230903212650106521892016798987454123467612430
+12332102107812121786787430752105678901960013438900421
+01489237876543080695890124567234787017871012543321530
+90574323965012891234301233208943296323702387654487651
+87665010121026700343210120112350185410213498703599341
+96556901212345619656903234013461234554396569812678210
+03467832303434328743874105684570789689487876101432387
+12346345694540345012565106799688778776536964566501498
+01653210789691236522210239888799669890123453677890567
+18764101988780987121329845677234550187652122989108906
+89765001877101071030456776540112341290343001010267210
+67896982769612132549105689432101032301234578981354310
+78767853458743247678014988654312121000225665432458981
+69656765432658958976529812763243029810116767898567652
+30345899891067867789438701890156710723209852101438943
+21230014780890986290105610981260823654367643067324321
+10101423634761870121234327876501994569498543458015100
+45672344543052765436543234566782987678534412109176211
+34985495652143781287430110545093456767623303678989321
+43856784743430690398710325432112129865414510510076450
+32981012892121589459621234521001036772301623423165569
+01670143345023498764560149693456345681066739654234678
+12365294256510107643498238782347652397659848765985589
+03454385107898212532567345601098701498943707678876432
+12763476543789123431052101598709876510232110569845001
+29854307630076034521043015691612389323101023454032132
+38765218921165087654321126780543432134569878998108941
+47894356712234198765230105621234567023878565089237650
+21012349803343289890121234310123498012967432176546321