ztatiztikz 🤓

2024/04/p1/main.rs

@@ -1,33 +1,63 @@
-use std::{fs::File, io::Read, time::Instant};
+use std::{
+    cmp,
+    fs::File,
+    io::Read,
+    time::{Duration, Instant},
+};
 
 fn main() -> std::io::Result<()> {
     let args: Vec<_> = std::env::args().collect();
     let filename = &args[1];
+    let runs: u32 = args[2]
+        .parse()
+        .expect("did not receive a number as `runs` argument");
 
     let mut contents = vec![];
     let mut file = File::open(filename)?;
     file.read_to_end(&mut contents)?;
-
-    let directions: &[(isize, isize)] = &[
-        (-1, -1),
-        (-1, 0),
-        (-1, 1),
-        (0, -1),
-        (0, 1),
-        (1, -1),
-        (1, 0),
-        (1, 1),
-    ];
-
-    let a = Instant::now();
-
     let lines: Vec<_> = contents.split(|&b| b == b'\n').collect();
+
+    let mut max = Duration::ZERO;
+    let mut avg = Duration::ZERO;
+    let mut min = Duration::MAX;
+    let result = run(&lines);
+    for i in 0..runs {
+        let a = Instant::now();
+        let run_result = run(&lines);
+        let b = Instant::now();
+        if result != run_result {
+            panic!(
+                "supposed result is {} but this run got {} after {} runs",
+                result, run_result, i
+            );
+        }
+
+        let d = b - a;
+        max = cmp::max(d, max);
+        min = cmp::min(d, min);
+        avg += d / runs;
+    }
+
+    println!("\x1b[0;34mtotal \x1b[1;33m{result}\x1b[0;34m\n  runs  \x1b[1;33m{runs:?}\x1b[0;34m\n  avg.  \x1b[1;35m{avg:?}\x1b[0;34m\n  max.  \x1b[1;31m{max:?}\x1b[0;34m\n  min.  \x1b[1;32m{min:?}\x1b[0m");
+    Ok(())
+}
+
+fn run(lines: &[&[u8]]) -> usize {
     let mut t = 0;
     for (i, ln) in lines.iter().enumerate() {
         for (j, &ch) in ln.iter().enumerate() {
             if ch == b'X' {
-                for dir in directions.iter() {
-                    let r = eq_in_dir(&lines, (j, i), *dir, "MAS".bytes());
+                for dir in [
+                    (-1, -1),
+                    (-1, 0),
+                    (-1, 1),
+                    (0, -1),
+                    (0, 1),
+                    (1, -1),
+                    (1, 0),
+                    (1, 1),
+                ] {
+                    let r = eq_in_dir(lines, (j, i), dir, "MAS".bytes());
                     if r {
                         t += 1;
                     }
@@ -35,17 +65,15 @@ fn main() -> std::io::Result<()> {
             }
         }
     }
-
-    let b = Instant::now();
-
-    println!("total {t} in {:?}", b - a);
-    Ok(())
+    t
 }
 
 macro_rules! pstve_try_bool {
     ($a:expr, $b:expr) => {{
         let r = $a + $b;
-        if r < 0 { return false; }
+        if r < 0 {
+            return false;
+        }
         r
     }};
 }
@@ -62,8 +90,12 @@ fn eq_in_dir(
 
     let new_1 = pstve_try_bool!(pos.1 as isize, dir.1) as usize;
     let new_0 = pstve_try_bool!(pos.0 as isize, dir.0) as usize;
-    let Some(ln) = buf.get(new_1) else { return false; };
-    let Some(ch) = ln.get(new_0) else { return false; };
+    let Some(ln) = buf.get(new_1) else {
+        return false;
+    };
+    let Some(ch) = ln.get(new_0) else {
+        return false;
+    };
 
     if must_match == *ch {
         eq_in_dir(buf, (new_0, new_1), dir, matches)