Day03 - part 1

diff --git a/data/day03.input b/data/day03.input
new file mode 100644 (file)
index 0000000..4bff9f2
--- /dev/null
+++ b/data/day03.input
@@ -0,0 +1,2 @@
+R997,D543,L529,D916,R855,D705,L159,U444,R234,U639,L178,D682,L836,U333,R571,D906,L583,U872,L733,U815,L484,D641,R649,U378,L26,U66,L659,D27,R4,U325,L264,D711,L837,D986,L38,U623,L830,D369,L469,D704,L302,U143,L771,U170,R237,U477,L251,D100,R561,D889,R857,D780,R258,D299,L975,D481,L692,D894,R847,D416,R670,D658,L537,U748,R468,D304,L263,D884,R806,D13,R288,U933,R4,U291,L809,D242,R669,D50,R106,D510,R409,U311,R101,D232,R370,D490,L762,D805,L981,D637,L987,U403,R965,U724,L404,D664,L687,U868,L808,D174,L363,D241,L54,D238,R444,U75,R683,U712,L759,D569,R349,D378,L576,U437,R137,D822,R21,D595,L602,U147,R959,U350,R964,U625,L718,U331,L252,D386,L251,U371,R973,D709,R915,D837,L7,U727,L501,D520,L626,U161,L287,D224,L821,U555,L312,U234,L335,D572,L113,U673,L615,D919,R925,U16,R211,U77,R630,U786,R850,D221,R939,U559,R887,U779,L222,D482,L252,D682,L904,U568,R317,D453,R689,D917,R845,U260,R69,U613,R528,D447,L791,D119,L268,U215,L806,U786,R465,D787,L792,D823,R526,D709,L362,D748,L518,U115,L898,U784,R893,U911,R98,U215,R828,D100,R153,U496,L938,D403,R886,D317,L849,D59,R156,D27,L64,D771,R956,U880,R313,D244,L483,D17,R72,U467,L475,D444,R554,D781,R524,D152,L771,U435,L622,D601,R733,D478,L686,D12,L525,D467,L302,D948,L966,U572,L303,U914,R54,D417,R635,D425,R640,D703,R17,D187,L195,U59,R166,D616,L557,U458,L743,D166,R328,D640,R908,D775,L151,D216,L964,D202,L534,D239,R998,U167,L604,D812,L527,U526,L640,U93,L733,D980,R607,D879,L593,D721,R454,U137,R683,D343,L38,D398,L81,U392,R821,U247,L361,D208,R763,D771,L515
+L1000,D189,L867,U824,L193,D12,R704,U83,R371,D858,L970,D56,R877,D448,R962,U239,R641,D198,L840,D413,R586,D920,R650,U919,R375,D540,L150,U995,R54,D200,R61,D974,R249,U893,R319,U930,R658,U680,R286,D186,R963,U553,L256,U629,L554,U576,R887,U595,R629,D680,L684,U556,L302,U348,R825,D252,L684,U705,L258,D72,R907,U702,L518,U440,R239,U258,R825,U27,L580,D613,R357,D468,R519,U833,L415,D822,L798,U904,R812,U76,R86,U252,R427,U637,L896,U147,L294,U381,R306,U423,L688,D336,R648,U677,L750,D218,L649,D360,R710,D64,R317,U232,R261,D167,L49,D138,L431,D505,L535,U294,L553,U969,L144,U227,R437,D397,R359,U848,L48,D992,R169,D580,L219,D525,R552,U546,R849,D722,R894,D735,L182,U570,R274,D349,R312,U430,R441,U183,R645,D308,L416,U333,L687,U202,L973,D736,R382,U260,L176,D207,R706,U52,L142,D746,L328,D413,R879,D429,L679,D695,L224,D462,R358,D124,L515,D629,L873,D759,L763,U28,R765,D426,L93,U927,L395,U243,L393,D488,L729,U100,R488,D83,R47,U92,L871,D410,R405,D993,R537,D10,L79,D218,L686,D563,L31,U885,L784,D462,L160,U345,R204,U275,R162,U164,R843,D578,R255,D456,L398,U470,L576,D973,L337,D971,R205,U264,R707,U975,L60,U270,R1,U808,R844,D884,L952,D435,L144,D374,R389,D741,R404,D398,R282,D807,L316,U136,L504,U720,R859,D925,L711,U343,L535,D978,R578,U636,L447,D298,R574,U590,L142,D802,L846,D617,L838,U362,R812,U295,L328,U162,L617,D857,L759,D251,L343,U394,R721,U320,R836,U726,L950,D612,R129,U549,L970,D87,L341,D269,L659,U550,R835,D318,L189,U278,R871,D62,R703,U807,L389,U824,R521,D175,L698,U313,L942,D810,L498,U18,R168,D111,R607
\ No newline at end of file

diff --git a/src/day02.rs b/src/day02.rs
index 76bc33e..9db5379 100644 (file)
--- a/src/day02.rs
+++ b/src/day02.rs
@@ -19,8 +19,8 @@ fn execute_op_code(code : &mut [i32]) -> i32 {
 \r
 pub fn find_noun_and_verb(code : &[i32]) -> i32 {\r
     loop {\r
-        for noun in 0..=99 {\r
-            for verb in 0..=99 {\r
+        for verb in 0..=99 {\r
+            for noun in 0..=99 {\r
                 let mut code_copy = Vec::from(code);\r
                 code_copy[1] = noun;\r
                 code_copy[2] = verb;\r

diff --git a/src/day03.rs b/src/day03.rs
new file mode 100644 (file)
index 0000000..a35ce3f
--- /dev/null
+++ b/src/day03.rs
@@ -0,0 +1,59 @@
+use std::iter::Iterator;\r
+use std::collections::HashSet;\r
+\r
+pub fn split_movements(movements: &str) -> Vec<&str> {\r
+    movements.split(',').collect()\r
+}\r
+\r
+pub fn manhattan_distance_from_cross_to_port(wire1: &[&str], wire2: &[&str]) -> i32 {\r
+    fn positions(wire: &[&str]) -> HashSet<(i32, i32)> {\r
+        let (mut x, mut y) = (0, 0);\r
+        let mut pos = HashSet::<(i32, i32)>::new();\r
+        for mov in wire {\r
+            let distance = mov[1..].parse::<i32>().unwrap();\r
+            match mov.chars().nth(0).unwrap() {\r
+                'U'      => { for y2 in y+1 ..= y + distance { pos.insert((x, y2)); } y += distance },\r
+                'D'      => { for y2 in y - distance .. y    { pos.insert((x, y2)); } y -= distance },\r
+                'R'      => { for x2 in x+1 ..= x + distance { pos.insert((x2, y)); } x += distance },\r
+                'L' | _  => { for x2 in x - distance .. x    { pos.insert((x2, y)); } x -= distance },\r
+            }\r
+        }\r
+        pos\r
+    }\r
+\r
+    let (positions_wire1, positions_wire2) = (positions(wire1), positions(wire2));\r
+    let cross: HashSet<_> = positions_wire1.intersection(&positions_wire2).collect();\r
+    cross.iter().map(|(x, y)| x.abs() + y.abs()).min().unwrap()\r
+}\r
+\r
+#[cfg(test)]\r
+mod tests {\r
+    use super::*;\r
+\r
+    #[test]\r
+    fn simple_cases() {\r
+        assert_eq!(\r
+            manhattan_distance_from_cross_to_port(\r
+                &split_movements("R8,U5,L5,D3"),\r
+                &split_movements("U7,R6,D4,L4")\r
+            ),\r
+            6\r
+        );\r
+\r
+        assert_eq!(\r
+            manhattan_distance_from_cross_to_port(\r
+                &split_movements("R75,D30,R83,U83,L12,D49,R71,U7,L72"),\r
+                &split_movements("U62,R66,U55,R34,D71,R55,D58,R83")\r
+            ),\r
+            159\r
+        );\r
+\r
+        assert_eq!(\r
+            manhattan_distance_from_cross_to_port(\r
+                &split_movements("R98,U47,R26,D63,R33,U87,L62,D20,R33,U53,R51"),\r
+                &split_movements("U98,R91,D20,R16,D67,R40,U7,R15,U6,R7")\r
+            ),\r
+            135\r
+        );\r
+    }\r
+}
\ No newline at end of file

diff --git a/src/main.rs b/src/main.rs
index 83918d4..eff33ed 100644 (file)
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,10 @@
 use std::env;
+use std::fs;
 use std::time::Instant;
 
 mod day01;
 mod day02;
+mod day03;
 mod common;
 
 fn day01() -> String {
@@ -15,6 +17,15 @@ fn day02() -> String {
     format!("part1: {}, part2: {}", day02::execute_op_code_with_state_fixed(&mut Vec::from(&code[..])), day02::find_noun_and_verb(&code))
 }
 
+fn day03() -> String {
+    let file_content = fs::read_to_string("data/day03.input").unwrap();
+    let movements: Vec<&str> = file_content.lines().collect();
+    format!(
+        "part1: {}",
+        day03::manhattan_distance_from_cross_to_port(&day03::split_movements(&movements[0]), &day03::split_movements(&movements[1]))
+    )
+}
+
 fn do_day(days: &[fn() -> String], day: usize) {
     let now = Instant::now();
     println!("Result of day {}: {} (time: {} μs)", day, days[day - 1](), now.elapsed().as_micros());
@@ -25,7 +36,8 @@ fn main() {
 
     let days: Vec<fn() -> String> = vec!(
         day01,
-        day02
+        day02,
+        day03
     );
 
     let args: Vec<String> = env::args().skip(1).collect();