4 files changed, 86 insertions, 0 deletions
diff --git a/day02/.gitignore b/day02/.gitignore
new file mode 100644
index 0000000..9cd70c0
--- /dev/null
+++ b/day02/.gitignore
@@ -0,0 +1,3 @@
+/target
+/input.txt
+/example*.txt
+\ No newline at end of file
diff --git a/day02/Cargo.lock b/day02/Cargo.lock
new file mode 100644
index 0000000..2762917
--- /dev/null
+++ b/day02/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "day02"
+version = "0.1.0"
diff --git a/day02/Cargo.toml b/day02/Cargo.toml
new file mode 100644
index 0000000..3304419
--- /dev/null
+++ b/day02/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "day02"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
diff --git a/day02/src/main.rs b/day02/src/main.rs
new file mode 100644
index 0000000..ce21752
--- /dev/null
+++ b/day02/src/main.rs
@@ -0,0 +1,70 @@
+use std::io;
+
+struct Range {
+    start: i64,
+    end: i64,
+}
+
+impl Range {
+    fn new<'a>(mut iter: impl DoubleEndedIterator<Item = &'a str>) -> Self {
+        let start = iter.next().unwrap().parse::<i64>().unwrap();
+        let end = iter.next().unwrap().parse::<i64>().unwrap();
+        Self { start, end }
+    }
+}
+
+fn is_invalid(value: i64) -> bool {
+    let tmp = value.to_string();
+    /*
+    if tmp.len() % 2 != 0 {
+        return false
+    }
+    let (a, b) = tmp.split_at(tmp.len() / 2);
+    return a == b;
+     */
+    for x in 1..=tmp.len() / 2 {
+        if tmp.len() % x != 0 {
+            continue;
+        }
+        let (first, rest) = tmp.split_at(x);
+        let mut rest2 = rest;
+        let mut all_match = true;
+        for _ in 0..tmp.len() / x - 1 {
+            match rest2.strip_prefix(first) {
+                Some(value) => rest2 = value,
+                None => {
+                    all_match = false;
+                    break;
+                }
+            };
+        }
+        if all_match {
+            return true;
+        }
+    }
+    false
+}
+
+fn invalid(range: &Range) -> i64 {
+    let mut total = 0;
+    for i in range.start..=range.end {
+        if is_invalid(i) {
+            total += i;
+        }
+    }
+    total
+}
+
+fn main() {
+    let mut buffer = String::new();
+    io::stdin().read_line(&mut buffer).unwrap();
+    let mut total = 0;
+    for range in buffer
+        .trim_end()
+        .split(',')
+        .map(|x| Range::new(x.split('-')))
+    {
+        total += invalid(&range);
+    }
+    println!("Invalid: {}", total);
+}