Migrate to using cargo-aoc.

2020/src/bin/day1-input.txt

@@ -1,200 +0,0 @@
-1619
-1919
-1441
-1861
-1932
-1514
-1847
-1871
-1764
-1467
-1970
-1589
-2009
-1429
-1098
-1327
-1502
-1398
-1710
-1562
-1512
-1468
-1762
-1348
-1356
-1950
-1266
-1969
-1815
-1583
-1959
-1092
-1694
-1814
-1763
-1151
-1981
-1193
-1614
-1413
-1642
-1943
-1407
-895
-1430
-1706
-1962
-1522
-1486
-1986
-1623
-1489
-1411
-1851
-1817
-1416
-1654
-1438
-1419
-1649
-1362
-690
-1804
-1452
-1766
-1360
-1807
-1385
-1964
-1626
-1832
-745
-1702
-1602
-1471
-1996
-1915
-1813
-1460
-1925
-1638
-1581
-1584
-1379
-1148
-1554
-1564
-1914
-1757
-1820
-1559
-1096
-1944
-1587
-1499
-390
-1733
-1371
-1781
-2002
-324
-1655
-1639
-1482
-1198
-1264
-1953
-1320
-1704
-1321
-1449
-1455
-1509
-1765
-1797
-1703
-1758
-1610
-1756
-1901
-1707
-1968
-1601
-1328
-1336
-1592
-1678
-1699
-1793
-1957
-2000
-1306
-1094
-1545
-1331
-1751
-1739
-1335
-1753
-1983
-1966
-1934
-1831
-1426
-1711
-1840
-1857
-1347
-1789
-1409
-1310
-1752
-1897
-1497
-1485
-1125
-1803
-1577
-919
-1635
-1791
-1456
-1796
-1974
-1954
-1828
-2004
-1890
-1376
-1569
-1406
-1463
-2006
-1109
-1620
-1656
-1870
-1498
-1645
-1145
-1681
-1269
-1527
-1621
-1575
-1324
-1647
-1519
-1697
-1421
-1216
-1846
-1625
-1585
-1369
-1882
-1823
-1388
-1548
-1879

2020/src/bin/day1-test.txt

@@ -1,6 +0,0 @@
-1721
-979
-366
-299
-675
-1456

2020/src/day1.rs

@@ -30,98 +30,45 @@
 //!
 //! In your expense report, what is the product of the three entries that sum to 2020?
 
-use std::fs::File;
-use std::io::{BufRead, BufReader};
-use std::path::Path;
+use aoc_runner_derive::{aoc, aoc_generator};
 
-use anyhow::{anyhow, Result};
-
-fn main() -> Result<()> {
-    let path = std::env::args()
-        .nth(1)
-        .ok_or(anyhow!("Usage: 1 <path to expense report>"))?;
-    let nums = parse(path)?;
-    let pair = find_pair_2020(&nums).ok_or(anyhow!("Couldn't find pairs summing to 2020"))?;
-    println!("Product of {} x {} = {}", pair.0, pair.1, pair.0 * pair.1);
-    let triple = find_triple_2020(&nums).ok_or(anyhow!("Couldn't find triples summing to 2020"))?;
-    println!(
-        "Product of {} x {} x {} = {}",
-        triple.0,
-        triple.1,
-        triple.2,
-        triple.0 * triple.1 * triple.2
-    );
-    Ok(())
+/// Reads text file containing one integer per line, and parses them into `Vec<u32>`.  Any
+/// non-number will result in a panice.
+#[aoc_generator(day1)]
+fn parse(input: &str) -> Vec<u32> {
+    input
+        .split('\n')
+        .map(|line| line.parse().unwrap())
+        .collect()
 }
 
-/// Finds pairs of numbers in `nums` that sum to 2020.  If no pairs are found, `None` is returned.
-fn find_pair_2020(nums: &Vec<u32>) -> Option<(u32, u32)> {
+/// Finds pairs of numbers in `nums` that sum to 2020.  If no pairs are found, the function panics.
+/// TODO(wathiede): make a version that sorts or uses a hash for finding the match to compare
+/// benchmarks.
+#[aoc(day1, part1)]
+fn find_pair_2020(nums: &[u32]) -> u32 {
     for (idx, first) in nums.iter().enumerate() {
         for second in nums.iter().skip(idx + 1) {
             if first + second == 2020 {
-                return Some((*first, *second));
+                return first * second;
             }
         }
     }
-    None
+    panic!("Couldn't find pair");
 }
 
-/// Finds triple of numbers in `nums` that sum to 2020.  If no triple is found, `None` is returned.
-fn find_triple_2020(nums: &Vec<u32>) -> Option<(u32, u32, u32)> {
+/// Finds triple of numbers in `nums` that sum to 2020.  If no triple is found, the function
+/// panics.
+#[aoc(day1, part2)]
+fn find_triple_2020(nums: &[u32]) -> u32 {
     for (idx1, first) in nums.iter().enumerate() {
         for (idx2, second) in nums.iter().enumerate().skip(idx1 + 1) {
             for third in nums.iter().skip(idx2 + 1) {
                 if first + second + third == 2020 {
-                    return Some((*first, *second, *third));
+                    return first * second * third;
                 }
             }
         }
     }
-    None
-}
-
-/// Reads text file containing one integer per line, and parses them into `Vec<u32>`.  Any
-/// non-number will result in an error returned.
-fn parse<P: AsRef<Path>>(path: P) -> Result<Vec<u32>> {
-    let f = File::open(path)?;
-    let f = BufReader::new(f);
-    let mut nums = Vec::new();
-    for line in f.lines() {
-        let num: u32 = line?.parse()?;
-        nums.push(num)
-    }
-    Ok(nums)
-}
-
-#[cfg(test)]
-mod tests {
-    use anyhow::Context;
-
-    use super::*;
-
-    fn get_nums() -> Vec<u32> {
-        let root = std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"));
-        let path = root.join("src/bin/day1-test.txt");
-        parse(&path)
-            .with_context(|| format!("Input {}", path.display()))
-            .expect("failed to parse")
-    }
-
-    #[test]
-    fn test_parse() {
-        let nums = get_nums();
-        assert_eq!(nums, vec![1721, 979, 366, 299, 675, 1456]);
-    }
-
-    #[test]
-    fn test_find_pair_2020() {
-        let nums = get_nums();
-        assert_eq!(find_pair_2020(&nums), Some((1721, 299)));
-    }
-
-    #[test]
-    fn test_find_triple_2020() {
-        let nums = get_nums();
-        assert_eq!(find_triple_2020(&nums), Some((979, 366, 675)));
-    }
+    panic!("Couldn't find triple");
 }

2020/src/lib.rs

@@ -0,0 +1,5 @@
+mod day1;
+
+use aoc_runner_derive::aoc_lib;
+
+aoc_lib! { year = 2020 }