diff --git a/src/day04.rs b/src/day04.rs
new file mode 100644
index 0000000..dd7b202
--- /dev/null
+++ b/src/day04.rs
@@ -0,0 +1,57 @@
+use aoc_runner_derive::{aoc, aoc_generator};
+#[derive(Debug)]
+pub struct Range(u8,u8);
+
+impl Range {
+    fn contains(&self, other: &Self) -> bool {
+        self.0 <= other.0 && self.1 >= other.1
+    }
+    fn overlaps(&self, other: &Self) -> bool {
+        (self.0 <= other.0 && other.0 <= self.1) || (self.0 <= other.1 && other.1 <= self.1)
+    }
+}
+
+fn parse_range(range: &str) -> Range {
+    let mut range = range.split('-').map(|v| v.parse().unwrap());
+    let start = range.next().unwrap();
+    let end = range.next().unwrap();
+    Range(start, end)
+}
+
+fn parse_line(line: &str) -> (Range, Range) {
+    let mut line = line.split(',');
+    let first = line.next().unwrap();
+    let second = line.next().unwrap();
+    (parse_range(first), parse_range(second))
+}
+
+#[aoc_generator(day4)]
+pub fn input_generator(input: &str) -> Vec<(Range, Range)> {
+    let mut ret = vec![];
+    for line in input.lines() {
+        ret.push(parse_line(line))
+    }
+    ret
+}
+
+#[aoc(day4, part1)]
+pub fn solve_part1(input: &[(Range, Range)]) -> usize {
+    let mut count = 0;
+    for (a, b) in input {
+        if a.contains(b) || b.contains(a) {
+            count += 1;
+        }
+    }
+    count
+}
+
+#[aoc(day4, part2)]
+pub fn solve_part2(input: &[(Range, Range)]) -> usize {
+    let mut count = 0;
+    for (a, b) in input {
+        if a.overlaps(b) || b.overlaps(a) {
+            count += 1;
+        }
+    }
+    count
+}
diff --git a/src/lib.rs b/src/lib.rs
index 6d55771..dfac4ac 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,4 +2,5 @@ use aoc_runner_derive::aoc_lib;
 pub mod day01;
 pub mod day02;
 pub mod day03;
+pub mod day04;
 aoc_lib! { year = 2022 }