day02

1 files changed, 55 insertions, 0 deletions

diff --git a/2024/day02.rs b/2024/day02.rs
new file mode 100644
index 0000000..c32aa19
--- /dev/null
+++ b/2024/day02.rs
@@ -0,0 +1,55 @@
+#![allow(dead_code)]
+#![allow(unused_variables)]
+#![allow(unused_mut)]
+use std::env;
+use std::fs::File;
+use std::io::Read;
+
+fn is_all_same(arr: &[bool]) -> bool {
+    arr.windows(2).all(|w| w[0] == w[1])
+}
+
+fn is_safe(arr: &[i32]) -> bool {
+    let diff: Vec<i32> = arr.windows(2).map(|w| w[0] - w[1]).collect();
+    let inc_ok = diff.iter().map(|a| (3 >= a.abs()) && (a.abs() >= 1)).all(|a|a);
+    let sign_ok = is_all_same(&diff.iter().map(|a| *a > 0).collect::<Vec<_>>());
+
+    inc_ok && sign_ok
+}
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    let filename = if args.len() == 1 {
+        "in/".to_owned() + args[0].split('/').last().unwrap() + ".pzl"
+    } else {
+        args[1].clone()
+    };
+    let mut f = File::open(filename).expect("cannot open file");
+    let mut content = String::new();
+    f.read_to_string(&mut content).expect("cannot read file");
+    let lines = content.trim_end().split("\n");
+
+    let mut res1 = 0;
+    let mut res2 = 0;
+    for line in lines {
+        let a: Vec<i32> = line.split(" ").map(|a| a.parse().unwrap()).collect();
+
+        if is_safe(&a) {
+            res1 += 1;
+            res2 += 1;
+        } else {
+            for i in 0..a.len() {
+                let mut b = a.clone();
+                b.remove(i);
+                if is_safe(&b) {
+                    res2 += 1;
+                    break;
+                }
+            }
+        }
+    }
+
+    println!("res1: {}", res1);
+    println!("res2: {}", res2);
+    assert_eq!(res1, 257);
+    assert_eq!(res2, 328);
+}