Apply some minor fixes to rwc starter code

week2/rwc/src/main.rs

@@ -3,10 +3,10 @@ use std::process;
 
 fn main() {
     let args: Vec<String> = env::args().collect();
-    if args.len() < 3 {
+    if args.len() < 2 {
         println!("Too few arguments.");
         process::exit(1);
     }
-    let filename1 = &args[1];
+    let filename = &args[1];
     // Your code here :)
 }