day01 both

src/utils.rs

@@ -0,0 +1,11 @@
+use std::fs::File;
+use std::io::prelude::*;
+
+pub fn read_file(path: &str) -> String {
+    let mut f = File::open(path).expect(&format!("file '{}' not found", path));
+
+    let mut contents = String::new();
+    f.read_to_string(&mut contents)
+        .expect("something went wrong reading the file");
+    contents
+}