Day 2, 3, and 4.

2017/02/Cargo.lock

@@ -0,0 +1,4 @@
+[[package]]
+name = "day-02"
+version = "0.1.0"
+

2017/02/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "day-02"
+version = "0.1.0"
+authors = ["logaritmisk <anders.e.olsson@gmail.com>"]
+
+[dependencies]

2017/02/input.txt

@@ -0,0 +1,16 @@
+278	1689	250	1512	1792	1974	175	1639	235	1635	1690	1947	810	224	928	859
+160	50	55	81	68	130	145	21	211	136	119	78	174	155	149	72
+4284	185	4499	273	4750	4620	4779	4669	2333	231	416	1603	197	922	5149	2993
+120	124	104	1015	1467	110	299	320	1516	137	1473	132	1229	1329	1430	392
+257	234	3409	2914	2993	3291	368	284	259	3445	245	1400	3276	339	2207	233
+1259	78	811	99	2295	1628	3264	2616	116	3069	2622	1696	1457	1532	268	82
+868	619	139	522	168	872	176	160	1010	200	974	1008	1139	552	510	1083
+1982	224	3003	234	212	1293	1453	3359	326	3627	3276	3347	1438	2910	248	2512
+4964	527	5108	4742	4282	4561	4070	3540	196	228	3639	4848	152	1174	5005	202
+1381	1480	116	435	980	1022	155	1452	1372	121	128	869	1043	826	1398	137
+2067	2153	622	1479	2405	1134	2160	1057	819	99	106	1628	1538	108	112	1732
+4535	2729	4960	241	4372	3960	248	267	230	5083	827	1843	3488	4762	2294	3932
+3245	190	2249	2812	2620	2743	2209	465	139	2757	203	2832	2454	177	2799	2278
+1308	797	498	791	1312	99	1402	1332	521	1354	1339	101	367	1333	111	92
+149	4140	112	3748	148	815	4261	138	1422	2670	32	334	2029	4750	4472	2010
+114	605	94	136	96	167	553	395	164	159	284	104	530	551	544	18

2017/02/src/main.rs

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+use std::io::{self, Read};
+
+
+type Data = Vec<Vec<u32>>;
+
+
+fn parse(input: &str) -> Data {
+    input
+        .lines()
+        .map(|line| {
+            line.split_whitespace()
+                .flat_map(|cell| cell.parse::<u32>())
+                .collect::<Vec<_>>()
+        })
+        .collect::<Vec<_>>()
+}
+
+fn checksum(data: &Data) -> u32 {
+    data.iter()
+        .map(|row| {
+            let max = row.iter().max().unwrap_or(&0);
+            let min = row.iter().min().unwrap_or(&0);
+
+            max - min
+        })
+        .sum()
+}
+
+fn divisible(data: &Data) -> u32 {
+    data.iter()
+        .map(|row| {
+            let mut iter = row.iter();
+
+            while let Some(a) = iter.next() {
+                for b in iter.clone() {
+                    if a % b == 0 {
+                        return a / b;
+                    } else if b % a == 0 {
+                        return b / a;
+                    }
+                }
+            }
+
+            0
+        })
+        .sum()
+}
+
+
+fn main() {
+    let mut input = String::new();
+
+    io::stdin()
+        .read_to_string(&mut input)
+        .expect("failed to parse input");
+
+    let data = parse(&input);
+
+    println!("checksum={}", checksum(&data));
+    println!("divisible={}", divisible(&data));
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_checksum() {
+        let input = "5 1 9 5\n\
+                     7 5 3\n\
+                     2 4 6 8";
+
+        let data = parse(input);
+
+        assert_eq!(checksum(&data), 18);
+    }
+
+    #[test]
+    fn test_divisible() {
+        let input = "5 9 2 8\n\
+                     9 4 7 3\n\
+                     3 8 6 5";
+
+        let data = parse(input);
+
+        assert_eq!(divisible(&data), 9);
+    }
+}