First commit for Rust work days 1&2

.gitignore

@@ -1,7 +1,4 @@
 # Generated by Cargo
 # will have compiled files and executables
-/target/
+**/target/
-
+**/data
-# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
-# More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
-Cargo.lock

2016/day01/src/main.rs

@@ -1,3 +1,86 @@
+use std::io::Read;
+use std::fs::File;
+
+fn turn(state: &(i32, i32), direction: &String) -> (i32, i32) {
+    match direction.as_ref() {
+        "R" => { // clockwise motion
+            (-1 * state.1, 1 * state.0)
+        },
+        "L" => { //rotate widdershins
+            (1 * state.1, -1 * state.0)
+        },
+        _ => {
+            println!("Invalid direction: {}", direction);
+            (state.0, state.1)
+        },
+    }
+}
+
+fn step(state: &(i32, i32), pos: &(i32, i32), dist: i32) -> (i32, i32) {
+    (pos.0 + state.0 * dist, pos.1 + state.1 * dist)
+}
+
+// fn state_to_direction(state: &(i32, i32)) -> String {
+//     match state.0 {
+//         1 => "N",
+//         -1 => "S",
+//         0 => {
+//             match state.1 {
+//                 1 => "E",
+//                 -1 => "W",
+//                 _ => "Invalid",
+//             }
+//         },
+//         _ => "Invalid",
+//     }
+// }
+
+fn part_1(input: &String) {
+    let mut state = (1, 0);
+    let mut pos = (0, 0);
+    for item in input.trim().split(", ") {
+        let (dir, dist) = item.split_at(1);
+        let dir: String = dir.to_string();
+        let dist: i32 = dist.parse::<i32>().unwrap();
+
+        state = turn(&state, &dir);
+        pos = step(&state, &pos, dist);
+
+        //println!("Moved {} {} to arrive at ({}, {})", dist, dir, pos.0, pos.1);
+    }
+    println!("Part 1: Ended up at ({}, {}), {} away from the start", pos.0, pos.1, pos.0.abs() + pos.1.abs());
+}
+
+fn part_2(input: &String) {
+    let mut state = (1, 0);
+    let mut positions: Vec<(i32, i32)> = vec![(0, 0)];
+
+    for item in input.trim().split(", ") {
+        let (dir, dist) = item.split_at(1);
+        let dir: String = dir.to_string();
+        let dist: i32 = dist.parse::<i32>().unwrap();
+
+        state = turn(&state, &dir);
+        let pos = step(&state, positions.last().unwrap(), dist);
+        print!("Move {} {} to ({}, {}) - ", dist, dir, pos.0, pos.1);
+        match positions.iter().position(|&p| p == pos) {
+            Some(v) => {
+                println!("Part 2: Stopped twice at ({}, {}) on element {}, {} away from the start", pos.0, pos.1, v, pos.0.abs() + pos.1.abs());
+                break;
+            },
+            None => {
+                println!("Did not match {} locations", positions.len());
+                positions.push(pos);
+            },
+        }
+    }
+}
+
 fn main() {
-    println!("Hello, world!");
+    let mut file = File::open("./data").expect("could not open file");
+    let mut input = String::new();
+    file.read_to_string(&mut input).expect("could not read file");
+
+    //part_1(&input);
+    part_2(&input);
 }

2016/day02/Cargo.lock

@@ -0,0 +1,4 @@
+[root]
+name = "day02"
+version = "0.1.0"
+

2016/day02/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "day02"
+version = "0.1.0"
+authors = ["Russell Champoux <russell.champoux@thomsonreuters.com>"]
+
+[dependencies]

2016/day02/src/main.rs

@@ -0,0 +1,99 @@
+use std::cmp;
+use std::io::Read;
+use std::fs::File;
+
+fn clamp(val: i32, lb: i32, ub: i32) -> i32 {
+    cmp::min(cmp::max(val, lb), ub)
+}
+
+fn state_to_val(state: (i32, i32)) -> i32 {
+    state.0 + 3 * state.1 + 1
+}
+
+fn state_to_new_val(state: (i32, i32)) -> char {
+    let val_map = [
+        [' ', ' ', '1', ' ', ' '],
+        [' ', '2', '3', '4', ' '],
+        ['5', '6', '7', '8', '9'],
+        [' ', 'A', 'B', 'C', ' '],
+        [' ', ' ', 'D', ' ', ' ']
+    ];
+    val_map[state.1 as usize][state.0 as usize]
+}
+
+fn part_1(input: &String) {
+    let mut state =  (1, 1);
+    // model a 3x3 grid that looks like
+    // 1 2 3
+    // 4 5 6
+    // 7 8 9
+    // where (0,0) starts in the upper left
+
+    //println!("Start at {}", state_to_val(state));
+    let mut answer = String::new();
+
+    for line in input.split('\n') {
+        for letter in line.trim().chars() {
+            match letter {
+                'R' => { state.0 = clamp(state.0 + 1, 0, 2); },
+                'L' => { state.0 = clamp(state.0 - 1, 0, 2); },
+                'U' => { state.1 = clamp(state.1 - 1, 0, 2); },
+                'D' => { state.1 = clamp(state.1 + 1, 0, 2); },
+                _ => println!("Unknown!")
+            }
+            //println!("Moved {} to {}", letter, state_to_val(state));
+        }
+        //println!("End on {}", state_to_val(state));
+        answer += &state_to_val(state).to_string();
+    }
+    println!("Part 1 answer is {}", answer);
+}
+
+fn part_2(input: &String) {
+    let mut state = (0, 2);
+    // model a 5x5 grid that looks like
+    //     1
+    //   2 3 4
+    // 5 6 7 8 9
+    //   A B C
+    //     D
+    // where blank spaces are invalid
+    let valid_map = [
+        [0, 0, 1, 0, 0],
+        [0, 1, 1, 1, 0],
+        [1, 1, 1, 1, 1],
+        [0, 1, 1, 1, 0],
+        [0, 0, 1, 0, 0]
+    ];
+    let mut answer = String::new();
+
+    for line in input.split('\n') {
+        for letter in line.trim().chars() {
+            let mut new_state = state;
+            match letter {
+                'R' => { new_state.0 = clamp(state.0 + 1, 0, 4); },
+                'L' => { new_state.0 = clamp(state.0 - 1, 0, 4); },
+                'U' => { new_state.1 = clamp(state.1 - 1, 0, 4); },
+                'D' => { new_state.1 = clamp(state.1 + 1, 0, 4); },
+                _ => println!("Unknown!")
+            }
+            // if this is a valid move position
+            if valid_map[new_state.1 as usize][new_state.0 as usize] == 1 {
+                state = new_state;
+                //println!("Moved {} to {}", letter, state_to_new_val(state));
+            }
+        }
+        //println!("End on {}", state_to_new_val(state));
+        answer.push(state_to_new_val(state));
+    }
+    println!("Part 2 answer is {}", answer);
+}
+
+fn main() {
+    let mut file = File::open("./data").expect("could not open file");
+    let mut input = String::new();
+    file.read_to_string(&mut input).expect("could not read file");
+
+    part_1(&input);
+    part_2(&input);
+}

README.md

@@ -1,2 +1,4 @@
 # AdventOfCode
 A repo for Advent of Code stuff
+
+Each day has its own directory. Input data for each day is saved in the corresponding directory.