diff --git a/Cargo.lock b/Cargo.lock
index 9223647..7e8746c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -182,6 +182,13 @@ dependencies = [
  "priority-queue",
 ]
 
+[[package]]
+name = "day-18"
+version = "0.0.0"
+dependencies = [
+ "indoc",
+]
+
 [[package]]
 name = "deprecate-until"
 version = "0.1.1"
diff --git a/day-18/Cargo.toml b/day-18/Cargo.toml
new file mode 100644
index 0000000..c1c3503
--- /dev/null
+++ b/day-18/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "day-18"
+version = "0.0.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+[dev-dependencies]
+indoc.workspace = true
diff --git a/day-18/src/bin/input.txt b/day-18/src/bin/input.txt
new file mode 100644
index 0000000..23db3ac
--- /dev/null
+++ b/day-18/src/bin/input.txt
@@ -0,0 +1,738 @@
+L 4 (#3db750)
+U 10 (#0e0433)
+L 5 (#526490)
+U 6 (#3e9193)
+L 4 (#526492)
+U 5 (#4418e3)
+L 5 (#3ad2e0)
+U 5 (#579f63)
+L 4 (#118202)
+D 5 (#411263)
+L 5 (#135ac2)
+U 4 (#1196f3)
+L 4 (#5df7d2)
+U 5 (#22e353)
+L 4 (#1615c2)
+U 5 (#17bc73)
+L 9 (#038720)
+U 6 (#16cff3)
+L 7 (#57beb0)
+U 4 (#16cff1)
+L 6 (#3da480)
+U 8 (#43bb73)
+R 4 (#2c2540)
+U 8 (#374033)
+R 9 (#4f95d0)
+U 7 (#374031)
+L 9 (#0ff0e0)
+U 8 (#12b433)
+L 3 (#29b7c0)
+U 5 (#57fa93)
+L 4 (#3b4d90)
+U 5 (#175463)
+L 7 (#2945d0)
+U 3 (#151b23)
+R 6 (#34c720)
+U 2 (#1f0a03)
+R 8 (#3d8772)
+U 4 (#3eba93)
+R 7 (#0e4442)
+U 2 (#012851)
+R 2 (#2618e2)
+U 8 (#5ca961)
+L 3 (#0a2972)
+U 3 (#5980f3)
+L 4 (#43a0a2)
+U 2 (#0450c3)
+L 8 (#09fae2)
+U 3 (#320053)
+R 4 (#52e1a0)
+U 4 (#03ce91)
+R 8 (#330070)
+U 3 (#03ce93)
+L 5 (#43c770)
+U 3 (#3d18a3)
+L 8 (#488e60)
+U 5 (#2d0d63)
+L 7 (#1e78d0)
+D 4 (#1680c3)
+L 9 (#31ee60)
+D 3 (#483563)
+L 4 (#0c6710)
+D 3 (#467ed3)
+R 3 (#02df40)
+D 2 (#1e2ad3)
+R 10 (#3f20c2)
+D 4 (#447ef3)
+L 5 (#3f20c0)
+D 7 (#07f723)
+L 6 (#1a71e2)
+D 7 (#23f173)
+L 2 (#079be2)
+D 2 (#5cd243)
+L 7 (#3d9fc2)
+D 3 (#107ee3)
+L 3 (#165230)
+D 4 (#69e463)
+L 9 (#2159c0)
+D 2 (#1dd863)
+L 4 (#47e9a0)
+D 4 (#1bff13)
+R 10 (#12df90)
+D 3 (#364e23)
+R 3 (#517e12)
+D 3 (#0a71a3)
+L 8 (#2edfe2)
+D 8 (#339f93)
+L 5 (#27d7e0)
+D 8 (#4a91f3)
+L 8 (#44e320)
+D 9 (#0ea943)
+L 4 (#13a2f0)
+D 5 (#6356e3)
+R 10 (#05f220)
+D 4 (#2644a3)
+R 8 (#65bb92)
+D 4 (#2ae573)
+R 10 (#65bb90)
+D 4 (#312573)
+L 8 (#3b10c0)
+D 6 (#154f21)
+L 5 (#018462)
+D 5 (#552bb1)
+L 7 (#018460)
+D 4 (#0a3be1)
+L 3 (#2efbf0)
+D 12 (#17a7c1)
+L 4 (#30d400)
+U 4 (#624c61)
+L 7 (#38d3f0)
+U 3 (#214351)
+L 11 (#027d02)
+U 4 (#3bdac1)
+L 7 (#027d00)
+U 6 (#13f621)
+R 6 (#1c4f70)
+U 6 (#1c1f81)
+R 5 (#30ce40)
+D 6 (#149481)
+R 7 (#0d93b0)
+U 5 (#491791)
+R 7 (#50ae60)
+U 5 (#128a91)
+L 4 (#1f7990)
+U 7 (#010331)
+L 6 (#253e60)
+U 6 (#1f2643)
+L 3 (#232c10)
+U 5 (#3d8083)
+L 6 (#294c32)
+U 10 (#3fcf53)
+L 3 (#294c30)
+U 7 (#1c9cd3)
+L 8 (#26b342)
+U 2 (#2107e3)
+L 6 (#26b340)
+U 6 (#3a17c3)
+L 8 (#232c12)
+D 6 (#3199c3)
+L 7 (#34c162)
+U 9 (#0a6463)
+L 4 (#2f5132)
+U 9 (#1ef1c3)
+R 6 (#2318c0)
+U 3 (#21b8f3)
+R 3 (#40f9d0)
+D 7 (#1a5473)
+R 4 (#28adf0)
+D 2 (#2e6181)
+R 7 (#00d3f2)
+U 9 (#355a41)
+R 3 (#00d3f0)
+D 10 (#1b04c1)
+R 2 (#0ddf40)
+D 3 (#298111)
+R 4 (#42a8e0)
+U 2 (#5b93c1)
+R 4 (#4282b0)
+U 11 (#25af91)
+R 3 (#0ff3e0)
+U 7 (#002661)
+R 5 (#365a20)
+U 10 (#3382c1)
+R 6 (#3a83a0)
+U 3 (#376591)
+R 7 (#0894a0)
+U 6 (#379891)
+R 5 (#44e3d0)
+U 3 (#41e791)
+R 6 (#0133c0)
+U 4 (#070071)
+R 4 (#0627e0)
+U 4 (#33bea1)
+R 7 (#456812)
+U 5 (#5ac051)
+R 7 (#4254e2)
+U 7 (#49a231)
+R 5 (#0e82b2)
+U 3 (#14b5a1)
+R 4 (#320942)
+D 8 (#126031)
+R 8 (#103262)
+U 7 (#3b7aa1)
+R 4 (#103260)
+U 5 (#30f9c1)
+R 5 (#29ced2)
+D 8 (#1ac681)
+R 7 (#62bf32)
+D 4 (#1a4041)
+R 4 (#14df02)
+U 8 (#443071)
+R 4 (#47db32)
+D 10 (#1b21b3)
+R 4 (#129c02)
+D 2 (#3e68b3)
+R 11 (#533d52)
+D 3 (#09d713)
+R 3 (#058242)
+D 6 (#52db63)
+L 7 (#1c7002)
+D 5 (#65d703)
+L 4 (#1c7000)
+D 7 (#0965f3)
+R 6 (#1c20e2)
+D 7 (#1d2273)
+R 5 (#4389b2)
+D 5 (#044e11)
+R 4 (#27a040)
+D 2 (#1178a1)
+R 6 (#120170)
+D 9 (#44ebc1)
+R 3 (#120172)
+D 9 (#152cc1)
+R 4 (#27a042)
+U 3 (#1f7081)
+R 12 (#2fcb02)
+U 2 (#1d0f31)
+R 8 (#42cb20)
+U 4 (#43ab11)
+L 4 (#42cb22)
+U 2 (#377091)
+L 9 (#3b2d12)
+U 3 (#1b21b1)
+L 7 (#51b2b2)
+U 6 (#3caf91)
+R 10 (#4018c2)
+U 5 (#2d7c51)
+L 5 (#525612)
+U 4 (#0c3071)
+L 4 (#16b6f2)
+D 6 (#400511)
+L 7 (#263730)
+U 6 (#13acb1)
+L 4 (#42d5d0)
+U 3 (#47f3a1)
+R 9 (#4018c0)
+U 7 (#154771)
+R 2 (#2fbd52)
+U 3 (#3a1df1)
+L 8 (#51aed2)
+U 7 (#4edb11)
+L 3 (#120e82)
+U 7 (#64c5f1)
+R 9 (#0937d2)
+U 4 (#1c4f21)
+R 7 (#4551f2)
+U 5 (#5a5493)
+R 4 (#1edfb2)
+U 5 (#169093)
+R 10 (#37eac2)
+D 3 (#188731)
+R 5 (#0f1a82)
+D 5 (#585df1)
+R 3 (#120232)
+D 2 (#2ae331)
+R 8 (#2287d2)
+D 5 (#103e81)
+R 6 (#4690b0)
+D 4 (#0772d3)
+R 7 (#3305c0)
+D 3 (#0772d1)
+L 10 (#38f400)
+D 6 (#380261)
+L 6 (#29e240)
+D 6 (#06f581)
+L 5 (#439b60)
+U 12 (#201da1)
+L 3 (#402420)
+D 6 (#144c91)
+L 9 (#22f100)
+D 4 (#3870e1)
+R 6 (#0c31f2)
+D 2 (#03ac33)
+R 3 (#5bc432)
+D 9 (#137063)
+R 3 (#26ea62)
+U 4 (#137061)
+R 6 (#450eb2)
+D 9 (#03ac31)
+R 5 (#43b222)
+U 9 (#05c961)
+R 5 (#4055d0)
+D 4 (#20af11)
+R 7 (#1c10f0)
+D 5 (#3943c1)
+R 2 (#26e682)
+D 4 (#1129c1)
+R 8 (#358042)
+D 4 (#070c01)
+R 5 (#2956d2)
+U 7 (#191821)
+R 3 (#224300)
+U 3 (#2af351)
+R 2 (#0feeb0)
+U 6 (#23cac1)
+L 5 (#5dfd50)
+U 5 (#2a7f41)
+L 3 (#527870)
+U 5 (#2a7f43)
+L 8 (#4aaf60)
+U 9 (#287f01)
+L 2 (#13a150)
+U 4 (#269d21)
+R 10 (#35e962)
+U 7 (#281351)
+R 8 (#35e982)
+U 4 (#281353)
+R 9 (#15be82)
+U 3 (#14d581)
+R 3 (#251f22)
+D 3 (#42a4e1)
+R 4 (#04bf90)
+D 9 (#1f56e3)
+R 6 (#3438d0)
+D 10 (#1f56e1)
+R 4 (#36fdd0)
+D 9 (#0cd891)
+L 4 (#38caa0)
+D 6 (#0cd893)
+R 6 (#11cc20)
+D 7 (#2ca3a1)
+L 6 (#3e7d60)
+D 7 (#271f11)
+R 4 (#20ba00)
+D 6 (#53c2b3)
+R 3 (#11a9f0)
+D 7 (#34ada3)
+R 8 (#567fe2)
+D 7 (#1f43f3)
+R 7 (#10e032)
+D 3 (#515b63)
+R 7 (#1a0d52)
+D 2 (#06c953)
+R 3 (#1bd910)
+D 8 (#339df3)
+R 6 (#483b90)
+D 8 (#2b9943)
+R 5 (#040ff0)
+D 8 (#249a13)
+R 2 (#4a2a82)
+D 2 (#2be7b3)
+R 10 (#1dfa12)
+U 4 (#23ec53)
+R 4 (#4e4080)
+U 4 (#431f73)
+R 7 (#332ce0)
+U 7 (#151433)
+L 6 (#532250)
+U 6 (#281c83)
+R 6 (#3b2fa0)
+U 3 (#580361)
+R 2 (#381920)
+U 4 (#423571)
+R 3 (#365c20)
+D 10 (#357b83)
+R 4 (#2bc910)
+U 10 (#17cef1)
+R 6 (#0d2f50)
+U 2 (#496f61)
+R 5 (#0d2f52)
+U 4 (#0a78e1)
+L 5 (#0db930)
+U 6 (#057ac3)
+L 5 (#065930)
+D 6 (#4034b3)
+L 5 (#065932)
+U 5 (#2607c3)
+L 3 (#3772f0)
+U 6 (#260ff3)
+R 6 (#0a16c2)
+U 5 (#0984c3)
+L 6 (#4ebf82)
+U 5 (#0984c1)
+L 4 (#181ef2)
+U 9 (#1d1d53)
+R 4 (#384730)
+U 2 (#219013)
+R 6 (#065250)
+U 6 (#2232b1)
+R 5 (#3f4030)
+U 5 (#471ca1)
+R 6 (#33c210)
+U 3 (#37cbe1)
+L 7 (#53b020)
+U 6 (#070661)
+R 6 (#2199f0)
+U 9 (#1d8d61)
+L 6 (#35c702)
+U 4 (#13cc81)
+R 7 (#22f592)
+U 3 (#36f1d1)
+R 6 (#17d3d2)
+D 7 (#4a1db1)
+R 4 (#161810)
+D 12 (#019c31)
+R 4 (#46b5a0)
+U 9 (#4bc491)
+R 4 (#13c2b0)
+U 2 (#07bdd1)
+R 4 (#1bce00)
+U 8 (#48c791)
+R 5 (#54aa00)
+U 3 (#079a91)
+R 5 (#19b550)
+D 4 (#2ff601)
+R 7 (#1560c2)
+D 10 (#3afde1)
+R 5 (#1560c0)
+D 5 (#19b1e1)
+R 4 (#29d140)
+D 2 (#1c83b3)
+R 6 (#274ae0)
+D 9 (#4f3ae3)
+R 4 (#2e2280)
+U 7 (#12aea3)
+R 3 (#121630)
+U 9 (#590343)
+R 5 (#121632)
+D 8 (#0f1813)
+R 8 (#2e2282)
+D 5 (#01f683)
+R 4 (#0b3350)
+D 8 (#2582f3)
+R 2 (#358bc0)
+D 8 (#495e93)
+R 2 (#2b6380)
+D 6 (#202a83)
+R 2 (#025d40)
+D 4 (#0600f1)
+R 6 (#492c30)
+D 9 (#310791)
+L 8 (#06d2c0)
+D 4 (#328091)
+L 2 (#060230)
+D 6 (#1d2163)
+R 10 (#04a2c0)
+D 4 (#201cc1)
+R 5 (#047b62)
+D 4 (#0e0ec1)
+R 4 (#17bd32)
+D 7 (#560041)
+R 3 (#41b672)
+D 5 (#1c40b1)
+R 9 (#01fea2)
+D 4 (#018691)
+L 7 (#13d742)
+D 4 (#56c211)
+L 5 (#2f7662)
+U 4 (#0e8e01)
+L 3 (#46d980)
+D 5 (#402761)
+L 7 (#1e38e0)
+D 8 (#402763)
+R 3 (#3e28e0)
+D 8 (#075c91)
+R 3 (#4cd990)
+D 2 (#1c83b1)
+R 6 (#0df200)
+U 6 (#4877c3)
+R 2 (#0ab900)
+U 4 (#5d14b3)
+R 8 (#3f7a60)
+D 5 (#061dd3)
+R 6 (#265810)
+U 3 (#4d7453)
+R 4 (#113c80)
+U 4 (#300853)
+L 6 (#45ab00)
+U 2 (#1ced03)
+L 6 (#0eace0)
+U 5 (#264f53)
+R 12 (#41dc40)
+U 3 (#199863)
+R 5 (#3b2dc2)
+U 10 (#0f4223)
+R 4 (#482cf2)
+D 5 (#1face3)
+R 8 (#321642)
+U 4 (#56f7a3)
+R 4 (#321640)
+U 10 (#2b6ef3)
+R 5 (#325182)
+D 5 (#4040a1)
+R 5 (#02d5b2)
+D 9 (#61d2d1)
+R 8 (#3d5d32)
+D 4 (#0f4221)
+L 7 (#176402)
+D 4 (#03b113)
+L 8 (#01d860)
+D 3 (#136273)
+L 7 (#206090)
+D 9 (#0ed183)
+R 3 (#21eee0)
+D 3 (#4b9c73)
+R 4 (#27e9e2)
+D 5 (#097b83)
+R 5 (#27e9e0)
+U 5 (#50f633)
+R 5 (#16b820)
+D 4 (#138331)
+R 5 (#34b750)
+D 8 (#5413f1)
+R 7 (#134940)
+D 7 (#4d4881)
+L 6 (#53aa40)
+D 7 (#00d6d1)
+L 5 (#0a3520)
+U 12 (#3c9a03)
+L 3 (#4c3bd0)
+U 5 (#3c9a01)
+L 7 (#24a000)
+D 10 (#0fb971)
+R 5 (#4631b2)
+D 3 (#3f5441)
+L 8 (#01d1e0)
+D 6 (#46ff21)
+R 8 (#3ee970)
+D 6 (#00a091)
+L 5 (#51a350)
+D 4 (#00a093)
+L 8 (#46c180)
+U 4 (#365041)
+L 2 (#47fbe2)
+U 4 (#226d01)
+R 4 (#67b392)
+U 10 (#226d03)
+L 4 (#191b92)
+U 4 (#416111)
+L 2 (#105522)
+U 7 (#5b2ce1)
+L 7 (#4631b0)
+D 8 (#334d41)
+L 7 (#1e4350)
+D 6 (#3021b1)
+L 3 (#299130)
+D 3 (#2b4123)
+L 3 (#414a00)
+U 5 (#2b4121)
+L 8 (#0fafb0)
+U 2 (#254f91)
+L 4 (#3b0f82)
+U 4 (#070d61)
+L 4 (#0a6292)
+U 6 (#070d63)
+L 6 (#3518d2)
+D 7 (#2b8b01)
+L 7 (#1a4b62)
+D 3 (#27a0c1)
+L 5 (#66c7d2)
+D 6 (#37f161)
+R 3 (#482732)
+D 5 (#1baa01)
+R 9 (#45b112)
+D 2 (#1baa03)
+R 6 (#07fad2)
+D 4 (#2f35a1)
+R 5 (#4d0002)
+D 6 (#1fa731)
+L 8 (#696b42)
+D 6 (#31c791)
+L 9 (#08fd42)
+D 2 (#0052f1)
+L 3 (#065eb2)
+D 5 (#2418b1)
+L 5 (#3dbd92)
+D 9 (#10bcf1)
+L 5 (#09a212)
+D 7 (#4ac071)
+L 2 (#0c2842)
+D 4 (#0299a1)
+L 6 (#39aa72)
+D 5 (#1eaff1)
+L 3 (#302492)
+U 4 (#4588d1)
+L 8 (#13af62)
+D 4 (#35a861)
+L 7 (#4c5b02)
+U 5 (#2dd353)
+L 3 (#0077d2)
+D 5 (#0ba793)
+L 12 (#38e632)
+D 5 (#476a13)
+L 5 (#35f252)
+U 7 (#5311a1)
+L 2 (#047cf2)
+U 8 (#267d63)
+R 4 (#0affa2)
+U 9 (#6a7183)
+R 4 (#25b702)
+U 7 (#0ab9d3)
+L 11 (#1dd902)
+U 2 (#0f0bd3)
+R 11 (#17dea2)
+U 6 (#0c2d03)
+R 5 (#18de02)
+D 11 (#52bf93)
+R 4 (#18de00)
+D 4 (#1199a3)
+R 4 (#0ddee2)
+U 3 (#063403)
+R 6 (#46dcc2)
+U 5 (#11b683)
+R 7 (#0f98c2)
+U 3 (#610763)
+R 6 (#17f292)
+U 6 (#312333)
+R 4 (#2fd3e2)
+U 4 (#083981)
+L 6 (#4b2332)
+U 5 (#083983)
+L 7 (#161f42)
+U 3 (#097733)
+R 8 (#079502)
+U 5 (#28a1b1)
+R 5 (#60e982)
+U 5 (#174aa1)
+L 4 (#60e980)
+U 7 (#2d1801)
+L 5 (#3a7fc2)
+U 6 (#267c01)
+L 8 (#10ae32)
+U 5 (#64c141)
+L 3 (#39bea2)
+U 4 (#0061e1)
+L 2 (#03c742)
+U 9 (#00fa21)
+L 5 (#3f4a42)
+D 13 (#0048e1)
+L 3 (#21f600)
+U 5 (#13e0d1)
+L 5 (#57fcf0)
+D 5 (#13e0d3)
+L 9 (#4e0b20)
+U 5 (#2fbea1)
+L 10 (#1d7ee2)
+D 6 (#5a3821)
+L 4 (#187d12)
+D 6 (#02da81)
+L 5 (#39b022)
+D 6 (#1e48d1)
+L 5 (#0a01a2)
+D 3 (#4f90e1)
+L 7 (#0b91d2)
+D 6 (#269903)
+L 4 (#322902)
+U 5 (#412583)
+L 10 (#322900)
+D 5 (#07dcc3)
+L 4 (#416db2)
+D 2 (#0118f3)
+L 6 (#002942)
+D 3 (#46c203)
+R 10 (#1ec1c2)
+D 7 (#0b31d1)
+L 10 (#48d2b2)
+D 6 (#499a71)
+L 4 (#00dc22)
+D 3 (#1adf01)
+R 10 (#20c8b2)
+D 8 (#2376b3)
+L 10 (#34ebc2)
+D 8 (#119bd3)
+R 4 (#393252)
+D 12 (#3a98c3)
+L 3 (#6119f2)
+D 10 (#22a903)
+L 8 (#0f5442)
+U 9 (#4466f1)
+L 6 (#32ebf2)
+U 6 (#291b41)
+L 8 (#089fc2)
+U 3 (#171d13)
+L 6 (#4607a2)
+U 6 (#3a53d3)
+L 3 (#4607a0)
+D 4 (#1c1153)
+L 5 (#3aa062)
+D 3 (#07ed63)
+L 10 (#285362)
+D 3 (#2033d3)
+R 8 (#053532)
+D 7 (#550e63)
+R 7 (#233902)
+D 7 (#159493)
+L 3 (#428bc2)
+D 3 (#4d6bc3)
+R 10 (#434cf2)
+D 2 (#220413)
+R 5 (#3b8d52)
+D 5 (#2d9a53)
+L 6 (#24c242)
+D 6 (#192663)
+R 4 (#084250)
+D 5 (#42e773)
+L 4 (#580d40)
+D 3 (#221923)
+L 3 (#2c4a70)
+U 5 (#1955e3)
+L 2 (#22aa00)
+U 9 (#325ae3)
+L 4 (#45a220)
+D 5 (#1b6af3)
+L 5 (#2e7230)
+U 7 (#47b843)
+L 6 (#4786f0)
+U 8 (#004a03)
+L 8 (#25caa0)
+D 4 (#2857e3)
+L 6 (#2bc040)
+D 7 (#216fc3)
+L 5 (#28ac22)
+D 4 (#0c70e1)
+L 4 (#27c792)
+D 9 (#0c70e3)
+L 8 (#3ccc22)
+U 10 (#236703)
+L 5 (#248f22)
+U 5 (#351f23)
+L 8 (#1cdae2)
+U 9 (#196223)
+L 4 (#262512)
+U 5 (#18a9e1)
+L 6 (#374d42)
+U 9 (#35d761)
+L 3 (#1a1ad2)
+U 2 (#357863)
+L 5 (#124822)
+U 5 (#02f933)
+L 3 (#09dcf2)
+U 3 (#51fde3)
+L 8 (#09dcf0)
+U 7 (#41c033)
+L 6 (#1ddaf2)
+U 7 (#15c193)
+L 3 (#609412)
+U 7 (#0a4e23)
+L 8 (#2d99f2)
+U 5 (#01ac13)
\ No newline at end of file
diff --git a/day-18/src/bin/part1.rs b/day-18/src/bin/part1.rs
new file mode 100644
index 0000000..0c2f629
--- /dev/null
+++ b/day-18/src/bin/part1.rs
@@ -0,0 +1,124 @@
+fn main() {
+    println!("{}", part1(include_str!("./input.txt")));
+}
+
+fn part1(input: &str) -> i32 {
+    let instructions = input
+        .lines()
+        .map(|line| Instruction::try_from(line).expect("invalid instruction"))
+        .collect::<Vec<_>>();
+
+    let (corners, length) =
+        instructions
+            .iter()
+            .fold((vec![(0, 0)], 0), |(mut corners, length), instruction| {
+                let last_corner = corners.last().unwrap();
+                let new_corner = match instruction.direction {
+                    Direction::Up => (last_corner.0, last_corner.1 - instruction.distance),
+                    Direction::Down => (last_corner.0, last_corner.1 + instruction.distance),
+                    Direction::Left => (last_corner.0 - instruction.distance, last_corner.1),
+                    Direction::Right => (last_corner.0 + instruction.distance, last_corner.1),
+                };
+                corners.push(new_corner);
+                (corners, length + instruction.distance)
+            });
+
+    // shoelace formula with edges also du out
+    corners
+        .iter()
+        .zip(&corners[1..])
+        .map(|(v1, v2)| (v1.0 - v2.0) * (v1.1 + v2.1))
+        .sum::<i32>()
+        .abs()
+        / 2
+        + length / 2
+        + 1
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+struct Instruction {
+    direction: Direction,
+    distance: i32,
+    color: u32,
+}
+impl TryFrom<&str> for Instruction {
+    type Error = &'static str;
+
+    fn try_from(s: &str) -> Result<Self, Self::Error> {
+        let mut parts = s.split_whitespace();
+        let direction =
+            Direction::try_from(parts.next().expect("no direction").chars().next().unwrap())
+                .expect("invalid direction");
+        let distance = parts
+            .next()
+            .expect("no distance")
+            .parse::<i32>()
+            .expect("invalid distance");
+        let color = u32::from_str_radix(
+            parts
+                .next()
+                .expect("no color")
+                .trim_start_matches("(#")
+                .trim_end_matches(')'),
+            16,
+        )
+        .expect("invalid color");
+        Ok(Self {
+            direction,
+            distance,
+            color,
+        })
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+enum Direction {
+    Up,
+    Down,
+    Left,
+    Right,
+}
+impl TryFrom<char> for Direction {
+    type Error = &'static str;
+
+    fn try_from(c: char) -> Result<Self, Self::Error> {
+        match c {
+            'U' => Ok(Self::Up),
+            'D' => Ok(Self::Down),
+            'L' => Ok(Self::Left),
+            'R' => Ok(Self::Right),
+            _ => Err("invalid direction"),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use indoc::indoc;
+
+    #[test]
+    fn test_part1() {
+        assert_eq!(
+            part1(indoc!(
+                "
+                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)
+                "
+            )),
+            62
+        );
+    }
+}
diff --git a/day-18/src/bin/part2.rs b/day-18/src/bin/part2.rs
new file mode 100644
index 0000000..12eae14
--- /dev/null
+++ b/day-18/src/bin/part2.rs
@@ -0,0 +1,119 @@
+fn main() {
+    println!("{}", part2(include_str!("./input.txt")));
+}
+
+fn part2(input: &str) -> i64 {
+    let instructions = input
+        .lines()
+        .map(|line| Instruction::try_from(line).expect("invalid instruction"))
+        .collect::<Vec<_>>();
+
+    let (corners, length) =
+        instructions
+            .iter()
+            .fold((vec![(0, 0)], 0), |(mut corners, length), instruction| {
+                let last_corner = corners.last().unwrap();
+                let new_corner = match instruction.direction {
+                    Direction::Up => (last_corner.0, last_corner.1 - instruction.distance),
+                    Direction::Down => (last_corner.0, last_corner.1 + instruction.distance),
+                    Direction::Left => (last_corner.0 - instruction.distance, last_corner.1),
+                    Direction::Right => (last_corner.0 + instruction.distance, last_corner.1),
+                };
+                corners.push(new_corner);
+                (corners, length + instruction.distance)
+            });
+
+    // shoelace formula with edges also du out
+    corners
+        .iter()
+        .zip(&corners[1..])
+        .map(|(v1, v2)| (v1.0 - v2.0) * (v1.1 + v2.1))
+        .sum::<i64>()
+        .abs()
+        / 2
+        + length / 2
+        + 1
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+struct Instruction {
+    direction: Direction,
+    distance: i64,
+}
+impl TryFrom<&str> for Instruction {
+    type Error = &'static str;
+
+    fn try_from(s: &str) -> Result<Self, Self::Error> {
+        let mut parts = s.split_whitespace();
+        let hex = parts
+            .nth(2)
+            .expect("no color")
+            .trim_start_matches("(#")
+            .trim_end_matches(')');
+        let distance = i64::from_str_radix(&hex[0..5], 16).map_err(|_| "invalid distance")?;
+        let direction = match hex.chars().nth(5).ok_or("no direction")? {
+            '0' => Direction::Right,
+            '1' => Direction::Down,
+            '2' => Direction::Left,
+            '3' => Direction::Up,
+            _ => return Err("invalid direction"),
+        };
+
+        Ok(Self {
+            direction,
+            distance,
+        })
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+enum Direction {
+    Up,
+    Down,
+    Left,
+    Right,
+}
+impl TryFrom<char> for Direction {
+    type Error = &'static str;
+
+    fn try_from(c: char) -> Result<Self, Self::Error> {
+        match c {
+            'U' => Ok(Self::Up),
+            'D' => Ok(Self::Down),
+            'L' => Ok(Self::Left),
+            'R' => Ok(Self::Right),
+            _ => Err("invalid direction"),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use indoc::indoc;
+
+    #[test]
+    fn test_part2() {
+        assert_eq!(
+            part2(indoc!(
+                "
+                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)
+                "
+            )),
+            952408144115
+        );
+    }
+}