i hate d09p2

2025/09/p1.rs

@@ -0,0 +1,36 @@
+#[unsafe(no_mangle)]
+pub extern "Rust" fn challenge_usize(buf: &[u8]) -> usize {
+    // I do see how to make this in idk if O(n) or O(nlogn), but ima O(n^2) just at first
+    let coords = buf[..(buf.len() - 1)]
+        .split(|&b| b == b'\n')
+        .map(parse_ln)
+        .collect::<Vec<_>>();
+
+    let mut area = 0;
+    for coor1 in &coords {
+        for coor2 in &coords {
+            let dx = coor1.0.abs_diff(coor2.0) + 1;
+            let dy = coor1.1.abs_diff(coor2.1) + 1;
+            let this_area = dx * dy;
+
+            // println!(
+            //     "{},{} {},{} | {this_area}",
+            //     coor1.0, coor1.1, coor2.0, coor2.1
+            // );
+
+            area = area.max(this_area);
+        }
+    }
+
+    area
+}
+
+fn parse_ln(ln: &[u8]) -> (usize, usize) {
+    let mut iter = ln.split(|&b| b == b',').map(|slice| {
+        slice
+            .iter()
+            .fold(0, |acc, b| acc * 10 + (b - b'0') as usize)
+    });
+
+    (iter.next().unwrap(), iter.next().unwrap())
+}