diff --git a/18/Cargo.lock b/18/Cargo.lock
new file mode 100644
index 0000000..4c9e552
--- /dev/null
+++ b/18/Cargo.lock
@@ -0,0 +1,25 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day18"
+version = "0.1.0"
+dependencies = [
+ "itertools",
+]
+
+[[package]]
+name = "either"
+version = "1.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a26ae43d7bcc3b814de94796a5e736d4029efb0ee900c12e2d54c993ad1a1e07"
+
+[[package]]
+name = "itertools"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25db6b064527c5d482d0423354fcd07a89a2dfe07b67892e62411946db7f07b0"
+dependencies = [
+ "either",
+]
diff --git a/18/Cargo.toml b/18/Cargo.toml
new file mode 100644
index 0000000..4d457a8
--- /dev/null
+++ b/18/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "day18"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+itertools = "0.12.0"
diff --git a/18/input b/18/input
new file mode 100644
index 0000000..f27e001
--- /dev/null
+++ b/18/input
@@ -0,0 +1,640 @@
+L 4 (#248a72)
+U 3 (#295c13)
+L 4 (#49e802)
+U 5 (#5ff8b3)
+R 3 (#0df642)
+U 2 (#15b973)
+R 5 (#6cfb92)
+U 11 (#4e3cd3)
+L 4 (#422dd0)
+D 5 (#303fe3)
+L 7 (#6225e0)
+D 2 (#58bd63)
+L 9 (#6225e2)
+D 8 (#2b1703)
+L 6 (#422dd2)
+D 9 (#2eb9b3)
+L 2 (#10f270)
+D 10 (#0677b3)
+L 4 (#190450)
+U 11 (#55b4e3)
+L 4 (#361732)
+U 3 (#034663)
+L 4 (#37f902)
+U 6 (#19bb73)
+R 8 (#6e1030)
+U 8 (#4cad93)
+L 4 (#2509d0)
+U 6 (#1e1e61)
+L 5 (#3d3b90)
+U 8 (#28ec81)
+L 2 (#3f9200)
+U 5 (#437871)
+L 6 (#174bc0)
+D 5 (#3b58a1)
+L 11 (#064a60)
+U 5 (#539da3)
+L 4 (#1ea0d0)
+D 7 (#1909b3)
+L 2 (#296a52)
+D 9 (#6780c3)
+L 3 (#296a50)
+U 11 (#356893)
+L 2 (#0eb430)
+U 5 (#019203)
+L 5 (#4eea10)
+U 4 (#436533)
+L 4 (#20aeb0)
+U 4 (#2fb883)
+L 6 (#5046c0)
+U 11 (#392293)
+R 8 (#2567a0)
+U 3 (#57ee03)
+R 12 (#270540)
+U 2 (#358173)
+R 6 (#289e40)
+U 2 (#77b991)
+R 4 (#016c10)
+U 11 (#351091)
+R 2 (#714f90)
+U 6 (#4add71)
+L 11 (#00eab0)
+D 5 (#2f8361)
+L 8 (#192200)
+U 5 (#1416c1)
+L 13 (#775d30)
+U 3 (#3d3d63)
+L 8 (#6e4710)
+U 3 (#28cfd3)
+L 8 (#389880)
+U 5 (#28cfd1)
+L 7 (#4cd750)
+D 5 (#1d56e3)
+L 3 (#2789e2)
+D 5 (#5d7573)
+R 9 (#1b1372)
+D 5 (#1965a3)
+R 4 (#111052)
+D 2 (#5a2861)
+R 10 (#37f1c2)
+D 3 (#0b7ad1)
+R 5 (#012162)
+U 5 (#226f43)
+R 4 (#583cd2)
+D 5 (#4333f3)
+R 5 (#0eb952)
+D 3 (#22a273)
+L 2 (#34c5d0)
+D 3 (#355f11)
+L 5 (#13a460)
+D 4 (#355f13)
+L 6 (#3e2900)
+U 4 (#28d423)
+L 8 (#042432)
+D 3 (#4378f3)
+L 6 (#18a200)
+D 5 (#16a843)
+L 5 (#18a202)
+D 7 (#46fdd3)
+L 5 (#2a4802)
+D 5 (#2a4d23)
+L 5 (#6049d2)
+D 4 (#0a4023)
+L 4 (#09afb2)
+U 4 (#687713)
+L 5 (#4b85f2)
+D 4 (#0e1a53)
+L 8 (#331b60)
+U 6 (#270d83)
+L 6 (#331b62)
+U 6 (#25dba3)
+L 6 (#412e82)
+D 6 (#5e2e73)
+L 8 (#1de802)
+U 6 (#1e7143)
+L 4 (#4e7e82)
+U 3 (#160d63)
+L 5 (#19d230)
+U 3 (#36a4a3)
+R 3 (#19d232)
+U 6 (#4c63b3)
+R 10 (#0d2862)
+U 5 (#0ec351)
+R 11 (#593c62)
+U 6 (#12de21)
+R 2 (#08d482)
+U 4 (#277081)
+R 3 (#10eee0)
+U 4 (#382b91)
+L 4 (#512200)
+U 7 (#1279f1)
+L 3 (#229312)
+U 6 (#422721)
+R 6 (#71ddd2)
+U 6 (#093871)
+R 13 (#0d5622)
+D 5 (#093873)
+R 7 (#4c34e2)
+U 6 (#5b1743)
+R 2 (#4779a2)
+D 6 (#1cc6e3)
+R 7 (#3c13a0)
+U 5 (#3b60f3)
+R 4 (#3c13a2)
+U 9 (#229f83)
+R 3 (#0a6ff2)
+D 2 (#06d231)
+R 8 (#0298b2)
+D 11 (#4eb6a1)
+R 7 (#0298b0)
+U 8 (#438ce1)
+R 7 (#0e69e2)
+U 5 (#2d3e73)
+R 8 (#40b2c2)
+U 6 (#64cb53)
+L 2 (#40b2c0)
+U 3 (#0215c3)
+L 3 (#2cbf42)
+U 4 (#00c523)
+L 7 (#1fc3d2)
+D 4 (#68a633)
+L 5 (#1fc3d0)
+U 5 (#149853)
+L 5 (#2cbf40)
+U 9 (#0b9613)
+L 3 (#1e7f00)
+U 8 (#2fc533)
+L 7 (#3d7180)
+U 3 (#33f3a3)
+R 9 (#66d340)
+U 2 (#0fa1f1)
+R 4 (#0546c0)
+D 6 (#4c00b3)
+R 8 (#483b50)
+U 6 (#4c00b1)
+R 4 (#2fc7c0)
+U 2 (#0fa1f3)
+R 7 (#377280)
+U 6 (#200c43)
+R 5 (#429ef0)
+U 3 (#3a90f1)
+R 5 (#226142)
+U 4 (#2740c1)
+R 5 (#41ac62)
+U 3 (#275423)
+R 2 (#3ba072)
+U 11 (#275421)
+R 4 (#27ea92)
+D 8 (#402001)
+R 2 (#3456c0)
+D 6 (#5a4541)
+R 3 (#4d1400)
+U 4 (#5a4543)
+R 6 (#462de0)
+U 8 (#3fcdb1)
+R 6 (#1f2d90)
+U 6 (#4e7851)
+R 3 (#41eb30)
+D 6 (#4e7853)
+R 4 (#1aa1c0)
+D 10 (#0a4073)
+R 6 (#2134b2)
+D 7 (#164e43)
+R 4 (#200c72)
+D 5 (#3beca3)
+R 6 (#7445e0)
+U 3 (#2cda83)
+R 4 (#7445e2)
+U 3 (#475553)
+L 5 (#200c70)
+U 10 (#23fb33)
+R 5 (#2134b0)
+U 7 (#3c98d3)
+L 4 (#4cfc80)
+U 5 (#0f0e71)
+R 8 (#3c1d22)
+U 10 (#23a311)
+R 6 (#05da32)
+D 5 (#6229c1)
+R 5 (#41f750)
+D 8 (#1f4191)
+R 3 (#3530f0)
+D 13 (#4d3941)
+R 3 (#6215e0)
+D 9 (#2fe911)
+R 6 (#05cf90)
+U 4 (#25c901)
+R 2 (#335232)
+U 12 (#271371)
+R 2 (#335230)
+U 5 (#2bd1d1)
+L 9 (#1ffad0)
+U 6 (#6f6bc1)
+R 9 (#099600)
+U 5 (#13bee1)
+R 3 (#5aa820)
+U 3 (#3546c1)
+R 6 (#4dd5f0)
+D 11 (#495be1)
+R 6 (#60c8e0)
+U 11 (#4bd201)
+R 4 (#367f30)
+D 4 (#43dbc1)
+R 6 (#4bb740)
+U 12 (#07ce11)
+R 6 (#4b4d70)
+D 12 (#3e29e1)
+R 5 (#313fc0)
+U 4 (#293d51)
+R 4 (#1b4860)
+U 11 (#514571)
+R 4 (#5c11a2)
+U 4 (#444841)
+R 8 (#5c11a0)
+U 2 (#3e6c51)
+R 11 (#16dab0)
+U 7 (#26baf1)
+R 2 (#32e240)
+U 5 (#26baf3)
+R 6 (#2f0a70)
+U 6 (#11a821)
+R 3 (#527fc0)
+U 7 (#468b31)
+R 6 (#0641a0)
+U 10 (#20f351)
+R 7 (#547a90)
+U 12 (#1dbf11)
+R 2 (#17d0d2)
+U 10 (#159981)
+R 6 (#634e12)
+U 5 (#4ff021)
+R 10 (#006122)
+D 6 (#6589a3)
+R 3 (#1a74f2)
+D 2 (#19b911)
+R 12 (#3ed5f2)
+D 5 (#28ab31)
+R 3 (#09dd82)
+D 5 (#614c01)
+R 6 (#284d32)
+D 9 (#06b521)
+R 8 (#4dfad2)
+D 7 (#5b0f61)
+R 2 (#0fff22)
+D 5 (#1e6ff1)
+R 2 (#47b352)
+D 9 (#29c291)
+R 5 (#352ef2)
+D 3 (#042d11)
+R 4 (#262542)
+D 7 (#042d13)
+R 4 (#21e8f2)
+D 3 (#18cc21)
+R 3 (#16ed70)
+U 9 (#270ea1)
+R 7 (#4391e0)
+U 9 (#270ea3)
+R 4 (#22bdd0)
+D 3 (#3b72b1)
+R 7 (#1fd4b2)
+D 8 (#01bfe1)
+L 7 (#3d18a2)
+D 7 (#20dac1)
+R 4 (#67d990)
+D 4 (#1acd93)
+L 7 (#017410)
+D 2 (#6e4923)
+L 7 (#10bdd0)
+D 13 (#0650b3)
+L 2 (#072660)
+U 13 (#221151)
+L 6 (#41d720)
+D 3 (#5bc831)
+L 4 (#252450)
+D 9 (#118de1)
+R 6 (#05b1d0)
+D 4 (#247721)
+R 9 (#2b6b10)
+U 4 (#60da41)
+R 10 (#470c42)
+D 3 (#4fdc91)
+R 2 (#470c40)
+D 8 (#189db1)
+L 5 (#4a1f70)
+D 7 (#07e141)
+L 3 (#2524b0)
+D 5 (#2a6ce1)
+L 11 (#1a2e50)
+D 2 (#4f08c1)
+L 3 (#3b7ec0)
+D 9 (#65e011)
+L 8 (#24b9a0)
+D 6 (#196c61)
+L 5 (#540b20)
+D 6 (#243801)
+L 2 (#397ce0)
+D 3 (#411a41)
+L 12 (#397ce2)
+D 2 (#526d51)
+L 2 (#5b5810)
+D 5 (#2e96d3)
+L 8 (#6c4f80)
+U 6 (#274453)
+L 3 (#077010)
+U 5 (#37f603)
+R 5 (#73bf92)
+U 4 (#29ee73)
+R 11 (#5ffd40)
+U 5 (#3e12d3)
+L 4 (#4b4e32)
+U 12 (#114e01)
+L 2 (#45d0b2)
+U 4 (#114e03)
+L 6 (#4b8b02)
+U 9 (#3eff03)
+L 4 (#6968d0)
+U 4 (#3d4d33)
+L 6 (#1dd0e0)
+D 2 (#436023)
+L 9 (#58b812)
+D 6 (#423003)
+L 7 (#2e81a2)
+D 3 (#3d9e13)
+L 11 (#305450)
+D 6 (#2667f3)
+L 7 (#3a8470)
+D 8 (#293191)
+R 3 (#207ee0)
+D 4 (#293193)
+R 3 (#2c4360)
+D 4 (#2667f1)
+R 7 (#250ee0)
+U 4 (#70e1c3)
+R 4 (#2907d0)
+D 6 (#0b69a1)
+R 6 (#3babc0)
+D 6 (#7698c3)
+R 2 (#2752c0)
+D 3 (#7698c1)
+L 4 (#2dc550)
+D 11 (#4ec121)
+L 8 (#199d00)
+U 11 (#33f261)
+L 7 (#3b4e30)
+D 5 (#24e991)
+L 6 (#0aaeb2)
+U 9 (#15a993)
+L 5 (#59ed02)
+U 2 (#15a991)
+L 5 (#2c0432)
+U 10 (#337e81)
+L 7 (#248670)
+D 2 (#511d31)
+L 3 (#52ebc0)
+D 13 (#511d33)
+L 4 (#192db0)
+D 7 (#3dcf11)
+L 2 (#285030)
+D 3 (#15acc1)
+L 6 (#3a6c70)
+D 5 (#36f281)
+L 4 (#44fd02)
+U 5 (#4e8821)
+L 4 (#473972)
+U 5 (#2ab9f1)
+L 8 (#60aaa0)
+U 5 (#35c651)
+L 3 (#4736b2)
+U 10 (#4741d1)
+L 3 (#1973f2)
+U 5 (#1b5031)
+L 3 (#3c6532)
+D 5 (#49bd31)
+L 4 (#5e3f60)
+D 3 (#4a2011)
+L 4 (#2ba190)
+D 6 (#4a2013)
+L 3 (#653430)
+D 7 (#10dda1)
+L 11 (#2532d2)
+D 3 (#675311)
+L 4 (#27d642)
+D 6 (#02cae1)
+L 10 (#466652)
+D 7 (#34cef3)
+R 3 (#263692)
+D 7 (#34cef1)
+R 8 (#2c59d2)
+D 5 (#31afe1)
+L 8 (#091562)
+D 5 (#12c861)
+R 4 (#47a772)
+D 5 (#68a5b1)
+L 7 (#1f79a2)
+D 4 (#3b3c13)
+R 10 (#0e7122)
+D 4 (#087363)
+R 4 (#3e26c2)
+U 13 (#4953f3)
+R 3 (#5ac862)
+U 3 (#4953f1)
+R 3 (#13cfe2)
+D 5 (#087361)
+R 11 (#57f7a2)
+D 4 (#3b3c11)
+L 11 (#6dcb32)
+D 7 (#35e653)
+R 6 (#525282)
+D 5 (#3dac93)
+R 9 (#377082)
+D 6 (#2afda1)
+R 10 (#3e6422)
+D 10 (#220471)
+R 10 (#37ebf2)
+D 2 (#4d0213)
+R 5 (#2fa2f2)
+D 4 (#30df53)
+R 5 (#617e00)
+U 6 (#536393)
+R 5 (#496510)
+D 6 (#5f6733)
+R 4 (#3bf9b0)
+D 3 (#5f6731)
+R 4 (#48d940)
+D 3 (#35a5d3)
+R 4 (#284a82)
+D 9 (#445b23)
+L 4 (#2535c2)
+D 4 (#3f8b43)
+R 2 (#41a002)
+D 7 (#20b143)
+R 3 (#63ae42)
+U 8 (#328b03)
+R 9 (#383210)
+U 3 (#1ce143)
+R 7 (#383212)
+U 6 (#2ed603)
+R 5 (#00c512)
+U 6 (#6dea43)
+R 6 (#00c510)
+U 7 (#0f0643)
+R 3 (#4292a2)
+U 7 (#684961)
+R 3 (#03de80)
+U 5 (#46e0b1)
+R 6 (#3d4ae2)
+D 5 (#1d5fc1)
+R 7 (#3d4ae0)
+U 13 (#470ab1)
+R 5 (#03de82)
+U 4 (#282c71)
+R 6 (#5520f2)
+D 5 (#2f0981)
+R 2 (#5520f0)
+D 12 (#4081a1)
+R 6 (#22a272)
+U 5 (#284c53)
+R 8 (#081202)
+D 5 (#0b7831)
+R 4 (#3e4552)
+D 13 (#0b7833)
+R 5 (#38e092)
+U 11 (#284c51)
+R 2 (#550082)
+U 2 (#175033)
+R 6 (#036dc2)
+D 3 (#068791)
+R 9 (#3ff6f2)
+D 5 (#4a5783)
+R 13 (#4d5f92)
+D 6 (#3e3423)
+L 12 (#4f62d2)
+D 7 (#5e4363)
+L 3 (#0f7032)
+U 7 (#285261)
+L 12 (#4ea392)
+D 5 (#4c2dc1)
+L 4 (#0d2822)
+D 5 (#4c2dc3)
+R 9 (#518da2)
+D 2 (#41b3b1)
+R 7 (#023270)
+D 3 (#13d6e1)
+R 11 (#0874c0)
+D 3 (#2026c1)
+R 4 (#68f3a0)
+D 7 (#2026c3)
+L 8 (#208470)
+D 4 (#09bd81)
+L 3 (#193a10)
+D 7 (#5f3491)
+L 4 (#08cad2)
+D 10 (#068793)
+L 10 (#48acb2)
+D 4 (#20e341)
+L 7 (#6137a2)
+D 8 (#20e343)
+L 7 (#0bf292)
+D 7 (#5b5f13)
+L 8 (#2b2532)
+D 3 (#034073)
+L 5 (#3c7bb2)
+D 11 (#09c643)
+L 3 (#0d6e52)
+U 3 (#569d23)
+L 5 (#63fed0)
+U 4 (#162193)
+L 4 (#2eb310)
+U 3 (#655e23)
+L 10 (#42f8e0)
+U 4 (#341983)
+R 14 (#3dbbc0)
+U 5 (#551b13)
+L 5 (#2a94f0)
+U 6 (#05ae53)
+L 2 (#09db90)
+U 5 (#2c9e13)
+L 8 (#4c6d10)
+D 10 (#40ffb3)
+L 3 (#306c30)
+D 2 (#338911)
+L 6 (#4bed00)
+D 7 (#338913)
+R 7 (#12aae0)
+D 4 (#459613)
+L 7 (#75d3a2)
+D 7 (#37ad61)
+L 6 (#6dcf92)
+D 4 (#3b7703)
+R 9 (#0ee2b2)
+D 4 (#514c13)
+R 6 (#0ee2b0)
+D 3 (#2863b3)
+L 8 (#52eee2)
+D 8 (#2fc771)
+L 7 (#5be782)
+D 4 (#2f39a1)
+L 6 (#5be780)
+U 4 (#5625b1)
+L 2 (#5588c2)
+U 14 (#37ad63)
+L 3 (#0681e2)
+U 4 (#085481)
+L 3 (#037432)
+U 12 (#31ed51)
+L 4 (#6791e2)
+D 5 (#3546d3)
+L 6 (#4419e2)
+D 10 (#3546d1)
+L 4 (#2c1a72)
+D 10 (#5bead1)
+L 3 (#3b3252)
+D 9 (#3390c1)
+L 3 (#1d78c2)
+D 5 (#488d71)
+R 10 (#244042)
+D 2 (#10d1e1)
+R 5 (#3fd582)
+D 5 (#5025a1)
+L 3 (#381b70)
+D 11 (#771831)
+L 7 (#2abf50)
+U 11 (#17be81)
+L 5 (#1eb3c0)
+D 5 (#3d9c61)
+L 5 (#5f4de2)
+D 8 (#278361)
+L 2 (#2b95b2)
+D 9 (#2cb0b1)
+L 4 (#4a0182)
+D 6 (#2c6bb3)
+L 2 (#499642)
+D 5 (#4c76d3)
+L 8 (#2fe412)
+U 9 (#07b893)
+L 2 (#236d52)
+U 8 (#3956a3)
+L 7 (#34f252)
+U 3 (#52bbf1)
+L 7 (#189470)
+U 4 (#54b661)
+L 9 (#189472)
+U 7 (#0110f1)
+L 3 (#409bf2)
+U 3 (#46d3e3)
+L 5 (#4c0f82)
+U 11 (#215e73)
+L 4 (#4c0f80)
+U 7 (#4050f3)
+L 9 (#39b192)
+U 7 (#28b043)
+L 3 (#011270)
+U 7 (#1f6693)
+R 7 (#73c390)
+U 2 (#2c4113)
+R 5 (#0321c0)
+U 8 (#2f2903)
+L 12 (#5ab560)
+U 3 (#4dd983)
+L 6 (#38b7d2)
+U 12 (#03c8c3)
diff --git a/18/src/main.rs b/18/src/main.rs
new file mode 100644
index 0000000..eb6a54d
--- /dev/null
+++ b/18/src/main.rs
@@ -0,0 +1,312 @@
+use itertools::Itertools;
+use std::collections::{HashMap, LinkedList};
+use std::fmt::{Display, Write};
+use std::fs::File;
+use std::io::{BufRead, BufReader, Lines};
+use std::ops::Range;
+use std::time::Instant;
+
+// BOILERPLATE
+type InputIter = Lines<BufReader<File>>;
+
+fn get_input() -> InputIter {
+    let f = File::open("input").unwrap();
+    let br = BufReader::new(f);
+    br.lines()
+}
+
+fn main() {
+    let start = Instant::now();
+    let ans1 = problem1(get_input());
+    let duration = start.elapsed();
+    println!("Problem 1 solution: {} [{}s]", ans1, duration.as_secs_f64());
+
+    let start = Instant::now();
+    let ans2 = problem2(get_input());
+    let duration = start.elapsed();
+    println!("Problem 2 solution: {} [{}s]", ans2, duration.as_secs_f64());
+}
+
+// DATA
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Hash)]
+enum Direction {
+    Left,
+    Right,
+    Up,
+    Down,
+}
+
+impl Direction {
+    const fn all() -> &'static [Self; 4] {
+        &[
+            Direction::Left,
+            Direction::Right,
+            Direction::Up,
+            Direction::Down,
+        ]
+    }
+    const fn opposite(&self) -> Self {
+        match self {
+            Direction::Left => Direction::Right,
+            Direction::Right => Direction::Left,
+            Direction::Up => Direction::Down,
+            Direction::Down => Direction::Up,
+        }
+    }
+    const fn offset(&self) -> (isize, isize) {
+        match self {
+            Direction::Left => (-1, 0),
+            Direction::Right => (1, 0),
+            Direction::Up => (0, -1),
+            Direction::Down => (0, 1),
+        }
+    }
+}
+
+impl From<&str> for Direction {
+    fn from(s: &str) -> Self {
+        match s {
+            "L" => Direction::Left,
+            "R" => Direction::Right,
+            "U" => Direction::Up,
+            "D" => Direction::Down,
+            s => panic!("{} is not a valid direction", s),
+        }
+    }
+}
+
+impl From<&Direction> for char {
+    fn from(dir: &Direction) -> Self {
+        match dir {
+            Direction::Left => '←',
+            Direction::Right => '→',
+            Direction::Up => '↑',
+            Direction::Down => '↓',
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+struct DigInstruction {
+    dir: Direction,
+    count: usize,
+    color: String,
+}
+
+impl From<&str> for DigInstruction {
+    fn from(s: &str) -> Self {
+        let mut parts = s.split_ascii_whitespace();
+        let (dir, count, color) = (
+            parts.next().unwrap(),
+            parts.next().unwrap(),
+            parts.next().unwrap(),
+        );
+        Self {
+            dir: dir.into(),
+            count: count.parse().unwrap(),
+            color: color.into(),
+        }
+    }
+}
+
+#[derive(Debug)]
+struct DigPlan {
+    instructions: Vec<DigInstruction>,
+}
+
+#[derive(Debug, Clone)]
+struct DigTile {
+    position: Position,
+    depth: usize,
+    color: String,
+}
+
+impl Default for DigTile {
+    fn default() -> Self {
+        Self {
+            position: (0, 0),
+            depth: 0,
+            color: "000000".into(),
+        }
+    }
+}
+
+type Position = (isize, isize);
+
+#[derive(Debug)]
+struct DigHole {
+    tiles_loop: LinkedList<DigTile>,
+    tiles_map: HashMap<Position, DigTile>,
+    x_range: Range<isize>,
+    y_range: Range<isize>,
+}
+
+impl DigHole {
+    fn new() -> Self {
+        DigHole {
+            tiles_loop: LinkedList::new(),
+            tiles_map: HashMap::new(),
+            x_range: 0..0,
+            y_range: 0..0,
+        }
+    }
+    fn pos_offset(&self, pos: Position, offset: (isize, isize)) -> Position {
+        (pos.0 + offset.0, pos.1 + offset.1)
+    }
+    fn run_plan(&mut self, plan: &DigPlan) {
+        // start position is 1m deep
+        let mut cur_pos = (0, 0);
+        let (mut max_x, mut max_y) = (0, 0);
+
+        self.tiles_loop.push_back(DigTile {
+            position: cur_pos,
+            depth: 1,
+            color: "000000".into(),
+        });
+        for i in &plan.instructions {
+            println!("instruction: {:?}", i);
+            for _ in 0..i.count {
+                println!("  cur_pos: {:?}", cur_pos);
+                cur_pos = (cur_pos.0 + i.dir.offset().0, cur_pos.1 + i.dir.offset().1);
+                (max_x, max_y) = (
+                    std::cmp::max(cur_pos.0, max_x),
+                    std::cmp::max(cur_pos.1, max_y),
+                );
+                self.tiles_loop.push_back(DigTile {
+                    position: cur_pos,
+                    depth: 1,
+                    color: i.color.to_owned(),
+                });
+            }
+        }
+        // 2d vec dimension is (max_x+1, max_y+1)
+        for tile in &self.tiles_loop {
+            self.x_range.start = std::cmp::min(self.x_range.start, tile.position.0);
+            self.x_range.end = std::cmp::max(self.x_range.end, tile.position.0 + 1);
+            self.y_range.start = std::cmp::min(self.y_range.start, tile.position.1);
+            self.y_range.end = std::cmp::max(self.y_range.end, tile.position.1 + 1);
+            self.tiles_map.insert(tile.position, tile.clone());
+        }
+        println!("{}", self);
+        self.fill_at(self.find_first_inside().unwrap());
+    }
+    fn fill_at(&mut self, pos: Position) {
+        println!("filling at {:?}", pos);
+        let mut to_fill = vec![pos];
+
+        while let Some(fill_pos) = to_fill.pop() {
+            if self.tiles_map.contains_key(&fill_pos) {
+                continue;
+            } else {
+                self.tiles_map.insert(
+                    fill_pos,
+                    DigTile {
+                        position: fill_pos,
+                        depth: 1,
+                        color: "000000".to_owned(),
+                    },
+                );
+            }
+            for new_pos in Direction::all()
+                .iter()
+                .map(|dir| self.pos_offset(fill_pos, dir.offset()))
+                .filter(|pos| !self.tiles_map.contains_key(&pos))
+            {
+                to_fill.push(new_pos);
+            }
+        }
+    }
+    fn find_first_inside(&self) -> Option<Position> {
+        for y in self.y_range.clone() {
+            let mut inside = false;
+            for x in self.x_range.clone() {
+                if self.tiles_map.contains_key(&(x, y)) && (!self.tiles_map.contains_key(&(x - 1, y)) || !self.tiles_map.contains_key(&(x+1, y)))
+                {
+                    inside = !inside;
+                }
+                if inside && !self.tiles_map.contains_key(&(x, y)) {
+                    return Some((x as isize, y as isize));
+                };
+            }
+        }
+        None
+    }
+}
+
+impl Display for DigHole {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        for y in self.y_range.clone() {
+            for x in self.x_range.clone() {
+                f.write_char(if (x, y) == (133, -267) {
+                    '*'
+                } else if self.tiles_map.contains_key(&(x, y)) {
+                    '#'
+                } else {
+                    '.'
+                })?;
+            }
+            writeln!(f)?;
+        }
+        Ok(())
+    }
+}
+
+impl<T: BufRead> From<Lines<T>> for DigPlan {
+    fn from(lines: Lines<T>) -> Self {
+        Self {
+            instructions: lines
+                .map(|line| DigInstruction::from(line.unwrap().as_str()))
+                .collect(),
+        }
+    }
+}
+
+// PROBLEM 1 solution
+
+fn problem1<T: BufRead>(input: Lines<T>) -> u64 {
+    let plan = DigPlan::from(input);
+    println!("{:?}", plan);
+    let mut dig = DigHole::new();
+    dig.run_plan(&plan);
+    println!("{}", dig);
+    dig.tiles_map.iter().count() as u64
+}
+
+// PROBLEM 2 solution
+fn problem2<T: BufRead>(input: Lines<T>) -> u64 {
+    0
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::*;
+    use std::io::Cursor;
+
+    const EXAMPLE: &str = &"R 6 (#70c710)
+D 5 (#0dc571)
+L 2 (#5713f0)
+D 2 (#d2c081)
+R 2 (#59c680)
+D 2 (#411b91)
+L 5 (#8ceee2)
+U 2 (#caa173)
+L 1 (#1b58a2)
+U 2 (#caa171)
+R 2 (#7807d2)
+U 3 (#a77fa3)
+L 2 (#015232)
+U 2 (#7a21e3)";
+
+    #[test]
+    fn problem1_example() {
+        let c = Cursor::new(EXAMPLE);
+        assert_eq!(problem1(c.lines()), 62);
+    }
+
+    #[test]
+    fn problem2_example() {
+        let c = Cursor::new(EXAMPLE);
+        assert_eq!(problem2(c.lines()), 0);
+    }
+}