boilerplate: improve duration printing

2/Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day2"
+version = "0.1.0"

2/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "day2"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

2/src/main.rs

@@ -0,0 +1,129 @@
+use std::fs::File;
+use std::io::{BufRead, BufReader, Lines};
+use std::time::{Duration, Instant};
+
+// BOILERPLATE
+type InputIter = Lines<BufReader<File>>;
+
+fn get_input() -> InputIter {
+    let f = File::open("input").unwrap();
+    let br = BufReader::new(f);
+    br.lines()
+}
+
+fn duration_format(duration: &Duration) -> String {
+    match duration.as_secs_f64() {
+        x if x > 1.0 => format!("{:.3}s", x),
+        x if x > 0.010 => format!("{:.3}ms", x * 1e3),
+        x => format!("{:.3}us", x * 1e6),
+    }
+}
+
+fn main() {
+    let start = Instant::now();
+    let ans1 = problem1(get_input());
+    let duration = start.elapsed();
+    println!(
+        "Problem 1 solution: {} [{}]",
+        ans1,
+        duration_format(&duration)
+    );
+
+    let start = Instant::now();
+    let ans2 = problem2(get_input());
+    let duration = start.elapsed();
+    println!(
+        "Problem 2 solution: {} [{}]",
+        ans2,
+        duration_format(&duration)
+    );
+}
+
+struct Reports {
+    reports: Vec<Vec<u64>>,
+}
+
+impl<T: BufRead> From<Lines<T>> for Reports {
+    fn from(lines: Lines<T>) -> Self {
+        let mut reports = Vec::new();
+        for line in lines.map(|i| i.unwrap()) {
+            reports.push(
+                line.split_ascii_whitespace()
+                    .map(|record| record.parse::<u64>().unwrap())
+                    .collect(),
+            )
+        }
+        Reports { reports }
+    }
+}
+
+impl Reports {
+    fn is_safe(report: &Vec<u64>) -> bool {
+        (report.iter().zip(report.iter().skip(1)).all(|(a, b)| a > b)
+            || report.iter().zip(report.iter().skip(1)).all(|(a, b)| a < b))
+            && report
+                .iter()
+                .zip(report.iter().skip(1))
+                .all(|(a, b)| a.abs_diff(*b) >= 1 && a.abs_diff(*b) <= 3)
+    }
+    fn count_safe(&self) -> u64 {
+        self.reports.iter().filter(|report| Self::is_safe(report)).count() as u64
+    }
+    fn is_dumb_dampened_safe(report: &Vec<u64>) -> bool {
+        if Self::is_safe(report) {
+            return true;
+        }
+        for i in 0..report.len() {
+            let mut new_vec = report.clone();
+            new_vec.remove(i);
+            if Self::is_safe(&new_vec) {
+                return true;
+            }
+        }
+        false
+    }
+    fn dampened_count_safe(&self) -> u64 {
+        self.reports
+            .iter()
+            .filter(|report| Self::is_dumb_dampened_safe(report))
+            .count() as u64
+    }
+}
+
+// PROBLEM 1 solution
+
+fn problem1<T: BufRead>(input: Lines<T>) -> u64 {
+    let reports = Reports::from(input);
+    reports.count_safe()
+}
+
+// PROBLEM 2 solution
+fn problem2<T: BufRead>(input: Lines<T>) -> u64 {
+    let reports = Reports::from(input);
+    reports.dampened_count_safe()
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::*;
+    use std::io::Cursor;
+
+    const EXAMPLE: &str = &"7 6 4 2 1
+1 2 7 8 9
+9 7 6 2 1
+1 3 2 4 5
+8 6 4 4 1
+1 3 6 7 9";
+
+    #[test]
+    fn problem1_example() {
+        let c = Cursor::new(EXAMPLE);
+        assert_eq!(problem1(c.lines()), 2);
+    }
+
+    #[test]
+    fn problem2_example() {
+        let c = Cursor::new(EXAMPLE);
+        assert_eq!(problem2(c.lines()), 4);
+    }
+}

boilerplate/src/main.rs

@@ -1,26 +1,28 @@
 use std::fs::File;
 use std::io::{BufRead, BufReader, Lines};
-use std::time::Instant;
+use std::time::{Duration, Instant};
 
 // BOILERPLATE
 type InputIter = Lines<BufReader<File>>;
 
-fn get_input() -> InputIter {
-    let f = File::open("input").unwrap();
-    let br = BufReader::new(f);
-    br.lines()
+fn duration_format(duration: &Duration) -> String {
+    match duration.as_secs_f64() {
+        x if x > 1.0 => format!("{:.3}s", x),
+        x if x > 0.010 => format!("{:.3}ms", x * 1e3),
+        x => format!("{:.3}us", x * 1e6),
+    }
 }
 
 fn main() {
     let start = Instant::now();
     let ans1 = problem1(get_input());
     let duration = start.elapsed();
-    println!("Problem 1 solution: {} [{}s]", ans1, duration.as_secs_f64());
+    println!("Problem 1 solution: {} [{}]", ans1, duration_format(&duration));
 
     let start = Instant::now();
     let ans2 = problem2(get_input());
     let duration = start.elapsed();
-    println!("Problem 2 solution: {} [{}s]", ans2, duration.as_secs_f64());
+    println!("Problem 2 solution: {} [{}]", ans2, duration_format(&duration));
 }
 
 // PROBLEM 1 solution