didn't commit the project files the first time :^P

day_4/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "advent_of_code_2022"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+rfd = "0.10.0"

day_4/src/main.rs

@@ -0,0 +1,55 @@
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
+struct Team {
+    first: Assignment,
+    second: Assignment
+}
+
+struct Assignment {
+    start: u32,
+    end: u32
+}
+
+fn parse_assignment(unparsed_assignment: &str) -> Assignment {
+    let parts:Vec<&str> = unparsed_assignment.split("-").collect();
+
+    return Assignment {start: parts[0].clone().parse::<u32>().unwrap(), end: parts[1].clone().parse::<u32>().unwrap()}; //this won't work but internet is down :/
+}
+
+fn check_contain(check_team: &Team) -> bool {
+    return (check_team.first.start <= check_team.second.start && check_team.first.end >= check_team.second.end) || (check_team.second.start <= check_team.first.start && check_team.second.end >= check_team.first.end)
+}
+
+fn check_overlap(check_team: &Team) -> bool {
+    return (check_team.first.start <= check_team.second.end && check_team.first.start >= check_team.second.start) || (check_team.second.start <= check_team.first.end && check_team.second.start >= check_team.first.start)
+}
+
+fn main() {
+    let mut contain_counter = 0;
+    let mut overlap_counter = 0;
+    let current_path = std::env::current_dir().unwrap();
+    let res = rfd::FileDialog::new().set_directory(&current_path).pick_file().unwrap();
+    let list = File::open(res.as_path()).unwrap();
+    let reader = BufReader::new(list);
+    for buffer in reader.lines() {
+        if let Ok(line) = buffer {
+            let assignments = line.split(",").collect::<Vec<&str>>(); //NOTE the ::<... part seems to be generic rust
+            //Rust can also get this typing from the var it's going to put the output in
+            // let assignments: Vec<&str> = line.split().collect();
+            let mut first_assignment = parse_assignment(assignments[0]);
+            let mut second_assignment = parse_assignment(assignments[1]);
+            let mut temp_team = Team {first: first_assignment, second: second_assignment};
+            if check_contain(&temp_team) {
+                contain_counter += 1;
+            }
+            if check_overlap(&temp_team) {
+                overlap_counter += 1;
+            }
+        }
+    }
+    println!("there should be {} containing teams", contain_counter);
+    println!("There should be {} overlapping teams", overlap_counter);
+}
+
+