Added day 6

src/main.rs

@@ -1,7 +1,7 @@
 mod solutions;
 mod utils;
 
-use std::error::Error;
+use std::{error::Error, sync::{Arc, Mutex}};
 
 use solutions::*;
 
@@ -12,6 +12,7 @@ fn main() -> Result<(), Box<dyn Error>> {
         Box::new(day03::Day03 {}),
         Box::new(day04::Day04 {}),
         Box::new(day05::Day05 {}),
+        Box::new(day06::Day06 {}),
     ];
 
     // Run through and generate solutions