Adds Day 6

resources/input6.txt

@@ -0,0 +1,2 @@
+Time:        62     64     91     90
+Distance:   553   1010   1473   1074

src/days/day6.rs

@@ -0,0 +1,98 @@
+use std::{path::Path, str::FromStr, iter::zip};
+
+use itertools::Itertools;
+
+use crate::{error::AdventError, input::read_into};
+
+struct Record {
+    time: u64,
+    distance: u64,
+}
+
+impl FromStr for Record {
+    type Err = AdventError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut lines = s.lines();
+        let time = lines
+            .nth(0).ok_or(AdventError("A zero'th row doesn't exist".into()))?
+            .trim()
+            .split_ascii_whitespace()
+            .skip(1)
+            .fold("".to_string(), |mut sb, s| {
+                sb.push_str(s);
+                sb
+            }).parse::<u64>()?;
+        
+        let distance = lines
+            .nth(0).ok_or(AdventError("A zero'th row doesn't exist".into()))?
+            .trim()
+            .split_ascii_whitespace()
+            .skip(1)
+            .fold("".to_string(), |mut sb, s| {
+                sb.push_str(s); 
+                sb
+            }).parse::<u64>()?;
+
+        Ok(Record{time, distance})
+    }
+}
+
+struct RecordsOverview {
+    records: Vec<Record>
+}
+
+impl FromStr for RecordsOverview {
+    type Err = AdventError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut lines = s.lines();
+        let times = lines
+            .nth(0).ok_or(AdventError("A zero'th row doesn't exist".into()))?
+            .trim()
+            .split_ascii_whitespace()
+            .skip(1)
+            .map(|s| -> Result<u64, AdventError> {
+                Ok(s.parse::<u64>()?)
+            })
+            .collect::<Result<Vec<u64>, AdventError>>()?;
+        
+        let distances = lines
+            .nth(0).ok_or(AdventError("A zero'th row doesn't exist".into()))?
+            .trim()
+            .split_ascii_whitespace()
+            .skip(1)
+            .map(|s| -> Result<u64, AdventError> {
+                Ok(s.parse::<u64>()?)
+            })
+            .collect::<Result<Vec<u64>, AdventError>>()?;
+        
+        let records: Vec<Record> = zip(times, distances).map(|(time, distance)| {
+            Record{time, distance}
+        }).collect_vec();
+        
+        Ok(RecordsOverview {
+            records
+        })
+    }
+}
+
+pub fn one() -> Result<u32, AdventError> {
+    let overview = read_into::<RecordsOverview>(Path::new("resources/input6.txt"))?;
+    Ok(overview.records.iter().fold(1, |acc, record| {
+        acc * ((0..(record.time + 1)).into_iter().map(|x| {
+            x * (record.time - x)
+        }).filter(|x| {
+            *x > record.distance
+        }).count() as u32)
+    }))
+}
+
+pub fn two() -> Result<u32, AdventError> {
+    let record = read_into::<Record>(Path::new("resources/input6.txt"))?;
+    Ok((0..(record.time + 1)).into_iter().map(|x| {
+        x * (record.time - x)
+    }).filter(|x| {
+        *x > record.distance
+    }).count() as u32) 
+}

src/days/mod.rs

@@ -2,4 +2,5 @@ pub mod day1;
 pub mod day2;
 pub mod day3;
 pub mod day4;
-pub mod day5;
+pub mod day5;
+pub mod day6;

src/main.rs

@@ -16,6 +16,7 @@ fn main() -> Result<(), AdventError> {
         (day3::one as fn() -> Result<u32, AdventError>, day3::two as fn() -> Result<u32, AdventError>),
         (day4::one as fn() -> Result<u32, AdventError>, day4::two as fn() -> Result<u32, AdventError>),
         (day5::one as fn() -> Result<u32, AdventError>, day5::two as fn() -> Result<u32, AdventError>),
+        (day6::one as fn() -> Result<u32, AdventError>, day6::two as fn() -> Result<u32, AdventError>),
     ];
 
     if env::args().len() != 3 {