1 files changed, 41 insertions, 0 deletions
diff --git a/src/bin/2020/day1.rs b/src/bin/2020/day1.rs
new file mode 100644
index 0000000..8e582d8
--- /dev/null
+++ b/src/bin/2020/day1.rs
@@ -0,0 +1,41 @@
+use advent_of_code::prelude::*;
+
+pub fn parse(fh: File) -> Result<Vec<u64>> {
+    Ok(parse::lines(fh).collect())
+}
+
+pub fn part1(ints: Vec<u64>) -> Result<u64> {
+    for i in &ints {
+        for j in &ints {
+            if i + j == 2020 {
+                return Ok(i * j);
+            }
+        }
+    }
+    Err(anyhow!("no numbers summing to 2020 found"))
+}
+
+pub fn part2(ints: Vec<u64>) -> Result<u64> {
+    for i in &ints {
+        for j in &ints {
+            for k in &ints {
+                if i + j + k == 2020 {
+                    return Ok(i * j * k);
+                }
+            }
+        }
+    }
+    Err(anyhow!("no numbers summing to 2020 found"))
+}
+
+#[test]
+fn test() {
+    assert_eq!(
+        part1(parse(parse::data(2020, 1).unwrap()).unwrap()).unwrap(),
+        445536
+    );
+    assert_eq!(
+        part2(parse(parse::data(2020, 1).unwrap()).unwrap()).unwrap(),
+        138688160
+    );
+}